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CWE-124
Buffer Underwrite ('Buffer Underflow')
The product writes to a buffer using an index or pointer that references a memory location prior to the beginning of the buffer.
CVE-2026-28419 (GCVE-0-2026-28419)
Vulnerability from cvelistv5 – Published: 2026-02-27 22:02 – Updated: 2026-03-02 21:54
VLAI
Title
Vim has Heap-based Buffer Underflow in Emacs tags parsing
Summary
Vim is an open source, command line text editor. Prior to version 9.2.0075, a heap-based buffer underflow exists in Vim's Emacs-style tags file parsing logic. When processing a malformed tags file where a delimiter appears at the start of a line, Vim attempts to read memory immediately preceding the allocated buffer. Version 9.2.0075 fixes the issue.
Severity
5.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/vim/vim/security/advisories/GH… | x_refsource_CONFIRM |
| https://github.com/vim/vim/commit/9b7dfa2948c9e1e… | x_refsource_MISC |
| https://github.com/vim/vim/releases/tag/v9.2.0075 | x_refsource_MISC |
| http://www.openwall.com/lists/oss-security/2026/02/27/8 |
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CVE-2026-41499 (GCVE-0-2026-41499)
Vulnerability from cvelistv5 – Published: 2026-04-29 18:01 – Updated: 2026-04-29 18:31
VLAI
Title
Wazuh: Multiple Heap-based NULL WRITE Buffer Underflows in parse_uname_string()
Summary
Wazuh is a free and open source platform used for threat prevention, detection, and response. From version 4.0.0 to before version 4.14.4, multiple heap-based out-of-bounds WRITE vulnerabilities exist in parse_uname_string() (remoted_op.c). This function processes OS identification data from agents and contains a dangerous code pattern that appears in 4 locations within the same function: writing to strlen(ptr) - 1 without checking for empty strings. When the string is empty, strlen() returns 0, and 0 - 1 wraps to SIZE_MAX due to unsigned integer underflow. Due to pointer arithmetic wrapping, SIZE_MAX effectively becomes -1, causing a write exactly 1 byte before the allocated buffer. This corrupts heap metadata (e.g., the chunk size field in glibc malloc), leading to heap corruption. This issue has been patched in version 4.14.4.
Severity
6.5 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/wazuh/wazuh/security/advisorie… | x_refsource_CONFIRM |
| https://github.com/wazuh/wazuh/releases/tag/v4.14.4 | x_refsource_MISC |
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CVE-2026-44631 (GCVE-0-2026-44631)
Vulnerability from cvelistv5 – Published: 2026-06-08 15:19 – Updated: 2026-06-08 22:32
VLAI
Title
Apache HTTP Server: Heap Underflow in `ap_regname` via Signed Char Overflow
Summary
Buffer Underwrite vulnerability in Apache HTTP Server on crafted regular expressions in the configuration.
This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67.
Users are recommended to upgrade to version 2.4.68, which fixes the issue.
Severity
9.8 (Critical)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-124 - Buffer Underwrite
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://httpd.apache.org/security/vulnerabilities… | vendor-advisory |
| http://www.openwall.com/lists/oss-security/2026/0… |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Apache Software Foundation | Apache HTTP Server |
Affected:
2.4.0 , ≤ 2.4.67
(semver)
|
Credits
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CVE-2026-5089 (GCVE-0-2026-5089)
Vulnerability from cvelistv5 – Published: 2026-05-12 16:14 – Updated: 2026-05-14 13:51
VLAI
Title
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read
Summary
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read.
The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer:
while ( colon >= ptr && *colon != ':' )
{
colon--;
}
if ( *colon == ':' ) *colon = '\0'; // colon may be ptr-1 here
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Severity
7.3 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-124 - Buffer Underwrite ('Buffer Underflow')
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://metacpan.org/release/TODDR/YAML-Syck-1.38… | release-notes |
| https://github.com/cpan-authors/YAML-Syck/issues/132 | issue-tracking |
| https://github.com/cpan-authors/YAML-Syck/pull/133 | issue-tracking |
| https://github.com/cpan-authors/YAML-Syck/commit/… | patch |
| http://www.openwall.com/lists/oss-security/2026/0… |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| TODDR | YAML::Syck |
Affected:
0 , < 1.38
(custom)
|
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],
"solutions": [
{
"lang": "en",
"value": "Upgrade to YAML::Syck version 1.38 or later."
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "YAML::Syck versions before 1.38 for Perl has an out-of-bounds read",
"x_generator": {
"engine": "cpansec-cna-tool 0.1"
}
}
},
"cveMetadata": {
"assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"assignerShortName": "CPANSec",
"cveId": "CVE-2026-5089",
"datePublished": "2026-05-12T16:14:21.951Z",
"dateReserved": "2026-03-28T19:33:37.653Z",
"dateUpdated": "2026-05-14T13:51:01.952Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
Mitigation
Phase: Requirements
Description:
- Choose a language that is not susceptible to these issues.
Mitigation
Phase: Implementation
Description:
- All calculated values that are used as index or for pointer arithmetic should be validated to ensure that they are within an expected range.
No CAPEC attack patterns related to this CWE.