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CVE-2026-105244 (GCVE-0-2026-105244)

Vulnerability from nvd – Published: 2026-10-06 19:52 – Updated: 2026-10-06 19:52

Title

Apache log4net: RemoteSyslogAppender silently deletes non-ASCII content

Summary

Improper Encoding or Escaping of Output vulnerability in the RemoteSyslogAppender of Apache log4net. Every character outside visible ASCII and space was removed from the record instead of being escaped, so non-ASCII text and control characters such as tabs disappeared without notice. A party whose data reaches a log message could make a distinct value look identical in the record, for example a user name holding a zero-width space logged as admin. Only applications that use RemoteSyslogAppender are affected. This issue affects Apache log4net: from 1.2.12 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-116 - Improper Encoding or Escaping of Output

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/q7649hhdodth…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.12 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 56a2e146e21ff4737e1ff3ec308810e667873947 , < 77717061b20d4346b6c0ce6b54643d85fb348bc7 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
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          "collectionURL": "https://nuget.org/packages",
          "defaultStatus": "unaffected",
          "packageName": "log4net",
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              "status": "affected",
              "version": "1.2.12",
              "versionType": "semver"
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CVE-2026-105243 (GCVE-0-2026-105243)

Vulnerability from nvd – Published: 2026-10-06 19:51 – Updated: 2026-10-06 19:51

Title

Apache log4net: Oversize EventLogAppender record silently discarded

Summary

Insufficient Logging vulnerability in the EventLogAppender of Apache log4net. Long messages were truncated to a fixed size that exceeds what the Windows Event Log accepts once the log and source names are counted, and the event log then stored nothing and reported nothing. A party whose data reaches a log message could suppress the whole record by making it long enough. Only applications on Windows that use EventLogAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-778 - Insufficient Logging

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/jr6fj5skv1vn…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 28fbfb25678c48a8cc5bc9b94ead0dddfc39ffed (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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          "collectionURL": "https://nuget.org/packages",
          "defaultStatus": "unaffected",
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          "vendor": "Apache Software Foundation",
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              "status": "affected",
              "version": "1.2.9",
              "versionType": "semver"
            }
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CVE-2026-105242 (GCVE-0-2026-105242)

Vulnerability from nvd – Published: 2026-10-06 19:50 – Updated: 2026-10-06 19:50

Title

Apache log4net: Request validation failure drops the event in the aspnet-request converter

Summary

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A sender could suppress the log record of their own request. Only applications on ASP.NET for .NET Framework whose layout uses %aspnet-request are affected. This issue affects Apache log4net: from 1.2.11 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-755 - Improper Handling of Exceptional Conditions

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/316	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/zg6dbqm4ztm7…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.11 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 243f1e9f3ee235955bade4b4fe664a903378719a , < 145203420c579a703008b4b723b6a080757f4964 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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    "cna": {
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          "collectionURL": "https://nuget.org/packages",
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CVE-2026-105241 (GCVE-0-2026-105241)

Vulnerability from nvd – Published: 2026-10-06 19:49 – Updated: 2026-10-06 19:49

Title

Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch

Summary

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content, and a truncated mail could be left in the pickup directory. A party whose data reaches a log message could suppress the records of other events. Only applications that use SmtpPickupDirAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-176 - Improper Handling of Unicode Encoding

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/hg8dgh3oy8bp…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 4d2e10f0908199604b4326f9df6d0b43b871e333 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

{
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      "affected": [
        {
          "collectionURL": "https://nuget.org/packages",
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CVE-2026-105240 (GCVE-0-2026-105240)

Vulnerability from nvd – Published: 2026-10-06 19:47 – Updated: 2026-10-06 19:47

Title

Apache log4net: NUL character truncates OutputDebugStringAppender records

Summary

Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was silently lost. A party whose data reaches a log message could hide the rest of that record. Only applications on Windows that use OutputDebugStringAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-158 - Improper Neutralization of Null Byte or NUL Character

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/gyw2d4ppy82t…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 6046fe9d7f353b49fe995361c071ec2eea8f7ef6 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-105239 (GCVE-0-2026-105239)

Vulnerability from nvd – Published: 2026-10-06 19:46 – Updated: 2026-10-06 19:58

Title

Apache log4net: NUL character truncates EventLogAppender records

Summary

Improper Neutralization of Null Byte or NUL Character vulnerability in the EventLogAppender of Apache log4net. A NUL character in logged content ended the Windows Event Log record at that point, so everything the layout rendered after it, including exception text and trailing fields, was silently not stored. A party whose data reaches a log message could hide the rest of that record. Only applications on Windows that use EventLogAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-06 19:58 UTC

CWE

CWE-158 - Improper Neutralization of Null Byte or NUL Character

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/9fx1qo5hc0tg…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < dc5855a0720c91590fd7a81d729ea01fdd69e000 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-40021 (GCVE-0-2026-40021)

Vulnerability from nvd – Published: 2026-04-10 15:44 – Updated: 2026-04-10 17:35

Title

Apache Log4net: Silent log event loss in XmlLayout and XmlLayoutSchemaLog4J due to unescaped XML 1.0 forbidden characters

Summary

Apache Log4net's XmlLayout https://logging.apache.org/log4net/manual/configuration/layouts.html#layout-list and XmlLayoutSchemaLog4J https://logging.apache.org/log4net/manual/configuration/layouts.html#layout-list , in versions before 3.3.0, fail to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets in MDC property keys and values, as well as the identity field that may carry attacker-influenced data. This causes an exception during serialization and the silent loss of the affected log event. An attacker who can influence any of these fields can exploit this to suppress individual log records, impairing audit trails and detection of malicious activity. Users are advised to upgrade to Apache Log4net 3.3.0, which fixes this issue.

Severity

6.3 (Medium)


                        
                          CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-10 17:32 UTC

CWE

CWE-116 - Improper Encoding or Escaping of Output

Assigner

apache mitre root Scorecard

References

6 references

URL	Tags
https://github.com/apache/logging-log4net/pull/280	patch
https://logging.apache.org/security.html#CVE-2026-40021	vendor-advisory
https://logging.apache.org/cyclonedx/vdr.xml	vendor-advisory
https://logging.apache.org/log4net/manual/configu…	related
https://lists.apache.org/thread/q8otftjswhk69n3kx…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Log4net	Affected: 0 , < 3.3.0 (nuget) cpe:2.3:a:apache:log4net::::::::

Credits

f00dat

Show details on NVD website

JSON

To clipboard

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CVE-2026-105244 (GCVE-0-2026-105244)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:52 – Updated: 2026-10-06 19:52

Title

Apache log4net: RemoteSyslogAppender silently deletes non-ASCII content

Summary

Improper Encoding or Escaping of Output vulnerability in the RemoteSyslogAppender of Apache log4net. Every character outside visible ASCII and space was removed from the record instead of being escaped, so non-ASCII text and control characters such as tabs disappeared without notice. A party whose data reaches a log message could make a distinct value look identical in the record, for example a user name holding a zero-width space logged as admin. Only applications that use RemoteSyslogAppender are affected. This issue affects Apache log4net: from 1.2.12 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-116 - Improper Encoding or Escaping of Output

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/q7649hhdodth…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.12 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 56a2e146e21ff4737e1ff3ec308810e667873947 , < 77717061b20d4346b6c0ce6b54643d85fb348bc7 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-105243 (GCVE-0-2026-105243)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:51 – Updated: 2026-10-06 19:51

Title

Apache log4net: Oversize EventLogAppender record silently discarded

Summary

Insufficient Logging vulnerability in the EventLogAppender of Apache log4net. Long messages were truncated to a fixed size that exceeds what the Windows Event Log accepts once the log and source names are counted, and the event log then stored nothing and reported nothing. A party whose data reaches a log message could suppress the whole record by making it long enough. Only applications on Windows that use EventLogAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-778 - Insufficient Logging

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/jr6fj5skv1vn…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 28fbfb25678c48a8cc5bc9b94ead0dddfc39ffed (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-105242 (GCVE-0-2026-105242)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:50 – Updated: 2026-10-06 19:50

Title

Apache log4net: Request validation failure drops the event in the aspnet-request converter

Summary

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A sender could suppress the log record of their own request. Only applications on ASP.NET for .NET Framework whose layout uses %aspnet-request are affected. This issue affects Apache log4net: from 1.2.11 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-755 - Improper Handling of Exceptional Conditions

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/316	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/zg6dbqm4ztm7…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.11 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 243f1e9f3ee235955bade4b4fe664a903378719a , < 145203420c579a703008b4b723b6a080757f4964 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-105241 (GCVE-0-2026-105241)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:49 – Updated: 2026-10-06 19:49

Title

Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch

Summary

Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net. Content that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content, and a truncated mail could be left in the pickup directory. A party whose data reaches a log message could suppress the records of other events. Only applications that use SmtpPickupDirAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-176 - Improper Handling of Unicode Encoding

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/hg8dgh3oy8bp…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 4d2e10f0908199604b4326f9df6d0b43b871e333 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-105240 (GCVE-0-2026-105240)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:47 – Updated: 2026-10-06 19:47

Title

Apache log4net: NUL character truncates OutputDebugStringAppender records

Summary

Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was silently lost. A party whose data reaches a log message could hide the rest of that record. Only applications on Windows that use OutputDebugStringAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-158 - Improper Neutralization of Null Byte or NUL Character

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/gyw2d4ppy82t…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 6046fe9d7f353b49fe995361c071ec2eea8f7ef6 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-105239 (GCVE-0-2026-105239)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:46 – Updated: 2026-10-06 19:58

Title

Apache log4net: NUL character truncates EventLogAppender records

Summary

Improper Neutralization of Null Byte or NUL Character vulnerability in the EventLogAppender of Apache log4net. A NUL character in logged content ended the Windows Event Log record at that point, so everything the layout rendered after it, including exception text and trailing fields, was silently not stored. A party whose data reaches a log message could hide the rest of that record. Only applications on Windows that use EventLogAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-06 19:58 UTC

CWE

CWE-158 - Improper Neutralization of Null Byte or NUL Character

Assigner

apache mitre root Scorecard

References

3 references

URL	Tags
https://github.com/apache/logging-log4net/pull/315	patch
https://github.com/apache/logging-log4net/commit/…	patch
https://lists.apache.org/thread.html/9fx1qo5hc0tg…	vendor-advisory

Impacted products

2 products

Vendor	Product	Version
Apache Software Foundation	Apache log4net	Affected: 1.2.9 , < 3.5.0 (semver)
Apache Software Foundation	Apache log4net	Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < dc5855a0720c91590fd7a81d729ea01fdd69e000 (git)

Credits

The Apache Software Foundation Claude Security Jan Friedrich

Show details on NVD website

JSON

To clipboard

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CVE-2026-40021 (GCVE-0-2026-40021)

Vulnerability from cvelistv5 – Published: 2026-04-10 15:44 – Updated: 2026-04-10 17:35

Title

Apache Log4net: Silent log event loss in XmlLayout and XmlLayoutSchemaLog4J due to unescaped XML 1.0 forbidden characters

Summary

Apache Log4net's XmlLayout https://logging.apache.org/log4net/manual/configuration/layouts.html#layout-list and XmlLayoutSchemaLog4J https://logging.apache.org/log4net/manual/configuration/layouts.html#layout-list , in versions before 3.3.0, fail to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets in MDC property keys and values, as well as the identity field that may carry attacker-influenced data. This causes an exception during serialization and the silent loss of the affected log event. An attacker who can influence any of these fields can exploit this to suppress individual log records, impairing audit trails and detection of malicious activity. Users are advised to upgrade to Apache Log4net 3.3.0, which fixes this issue.

Severity

6.3 (Medium)


                        
                          CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-10 17:32 UTC

CWE

CWE-116 - Improper Encoding or Escaping of Output

Assigner

apache mitre root Scorecard

References

6 references

URL	Tags
https://github.com/apache/logging-log4net/pull/280	patch
https://logging.apache.org/security.html#CVE-2026-40021	vendor-advisory
https://logging.apache.org/cyclonedx/vdr.xml	vendor-advisory
https://logging.apache.org/log4net/manual/configu…	related
https://lists.apache.org/thread/q8otftjswhk69n3kx…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Log4net	Affected: 0 , < 3.3.0 (nuget) cpe:2.3:a:apache:log4net::::::::

Credits

f00dat

Show details on NVD website

JSON

To clipboard

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Find a vulnerability

Search criteria ⓘ Use this form to refine search results.
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14 vulnerabilities found for Apache Log4net by Apache Software Foundation

CVE-2026-105244 (GCVE-0-2026-105244)

CVE-2026-105243 (GCVE-0-2026-105243)

CVE-2026-105242 (GCVE-0-2026-105242)

CVE-2026-105241 (GCVE-0-2026-105241)

CVE-2026-105240 (GCVE-0-2026-105240)

CVE-2026-105239 (GCVE-0-2026-105239)

CVE-2026-40021 (GCVE-0-2026-40021)

CVE-2026-105244 (GCVE-0-2026-105244)

CVE-2026-105243 (GCVE-0-2026-105243)

CVE-2026-105242 (GCVE-0-2026-105242)

CVE-2026-105241 (GCVE-0-2026-105241)

CVE-2026-105240 (GCVE-0-2026-105240)

CVE-2026-105239 (GCVE-0-2026-105239)

CVE-2026-40021 (GCVE-0-2026-40021)

Find a vulnerability

Search criteria ⓘ Use this form to refine search results. Full-text search supports keyword queries with ranking and filtering. You can combine vendor, product, and sources to narrow results. Enable “Apply ordering” to sort by date instead of relevance.

14 vulnerabilities found for Apache Log4net by Apache Software Foundation

CVE-2026-105244 (GCVE-0-2026-105244)

CVE-2026-105243 (GCVE-0-2026-105243)

CVE-2026-105242 (GCVE-0-2026-105242)

CVE-2026-105241 (GCVE-0-2026-105241)

CVE-2026-105240 (GCVE-0-2026-105240)

CVE-2026-105239 (GCVE-0-2026-105239)

CVE-2026-40021 (GCVE-0-2026-40021)

CVE-2026-105244 (GCVE-0-2026-105244)

CVE-2026-105243 (GCVE-0-2026-105243)

CVE-2026-105242 (GCVE-0-2026-105242)

CVE-2026-105241 (GCVE-0-2026-105241)

CVE-2026-105240 (GCVE-0-2026-105240)

CVE-2026-105239 (GCVE-0-2026-105239)

CVE-2026-40021 (GCVE-0-2026-40021)

Search criteria ⓘ Use this form to refine search results.
Full-text search supports keyword queries with ranking and filtering.
You can combine vendor, product, and sources to narrow results.
Enable “Apply ordering” to sort by date instead of relevance.