CWE-297
AllowedImproper Validation of Certificate with Host Mismatch
Abstraction: Variant · Status: Incomplete
The product communicates with a host that provides a certificate, but the product does not properly ensure that the certificate is actually associated with that host.
135 vulnerabilities reference this CWE, most recent first.
GHSA-72QJ-48G4-5XGX
Vulnerability from github – Published: 2025-05-07 17:32 – Updated: 2026-01-21 16:54Summary
When verifying SSL certificates, jruby-openssl is not verifying that the hostname presented in the certificate matches the one we are trying to connect to, meaning a MITM could just present any valid cert for a completely different domain they own, and JRuby wouldn't complain.
Details
n/a
PoC
An example domain bad.substitutealert.com was created to present the a certificate for the domain s8a.me. The following script run in IRB in CRuby 3.4.3 will fail with certificate verify failed (hostname mismatch), but will work just fine in JRuby 10.0.0.0 and JRuby 9.4.2.0, both of which use jruby-openssl version 0.15.3
require "net/http"
require "openssl"
uri = URI("https://bad.substitutealert.com/")
https = Net::HTTP.new(uri.host, uri.port)
https.use_ssl = true
https.verify_mode = OpenSSL::SSL::VERIFY_PEER
body = https.start { https.get(uri.request_uri).body }
puts body
Impact
Anybody using JRuby to make requests of external APIs, or scraping the web, that depends on https to connect securely
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "rubygems:jruby-openssl"
},
"ranges": [
{
"events": [
{
"introduced": "0.12.1"
},
{
"fixed": "0.15.4"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.jruby:jruby"
},
"ranges": [
{
"events": [
{
"introduced": "10.0.0.0"
},
{
"fixed": "10.0.0.1"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.jruby:jruby"
},
"ranges": [
{
"events": [
{
"introduced": "9.3.4.0"
},
{
"fixed": "9.4.12.1"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "RubyGems",
"name": "jruby-openssl"
},
"ranges": [
{
"events": [
{
"introduced": "0.12.1"
},
{
"fixed": "0.15.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-46551"
],
"database_specific": {
"cwe_ids": [
"CWE-295",
"CWE-297"
],
"github_reviewed": true,
"github_reviewed_at": "2025-05-07T17:32:54Z",
"nvd_published_at": "2025-05-07T17:15:58Z",
"severity": "MODERATE"
},
"details": "### Summary\nWhen verifying SSL certificates, jruby-openssl is not verifying that the hostname presented in the certificate matches the one we are trying to connect to, meaning a MITM could just present _any_ valid cert for a completely different domain they own, and JRuby wouldn\u0027t complain. \n\n### Details\nn/a\n\n### PoC\nAn example domain bad.substitutealert.com was created to present the a certificate for the domain s8a.me. The following script run in IRB in CRuby 3.4.3 will fail with `certificate verify failed (hostname mismatch)`, but will work just fine in JRuby 10.0.0.0 and JRuby 9.4.2.0, both of which use jruby-openssl version 0.15.3\n\n```ruby\nrequire \"net/http\"\nrequire \"openssl\"\n\nuri = URI(\"https://bad.substitutealert.com/\")\nhttps = Net::HTTP.new(uri.host, uri.port)\nhttps.use_ssl = true\nhttps.verify_mode = OpenSSL::SSL::VERIFY_PEER\n\nbody = https.start { https.get(uri.request_uri).body }\nputs body\n```\n\n### Impact\nAnybody using JRuby to make requests of external APIs, or scraping the web, that depends on https to connect securely",
"id": "GHSA-72qj-48g4-5xgx",
"modified": "2026-01-21T16:54:31Z",
"published": "2025-05-07T17:32:54Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/jruby/jruby-openssl/security/advisories/GHSA-72qj-48g4-5xgx"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-46551"
},
{
"type": "WEB",
"url": "https://github.com/jruby/jruby-openssl/commit/31a56d690ce9b8af47af09aaaf809081949ed285"
},
{
"type": "WEB",
"url": "https://github.com/jruby/jruby-openssl/commit/b1fc5d645c0d90891b8865925ac1c15e3f15a055"
},
{
"type": "PACKAGE",
"url": "https://github.com/jruby/jruby-openssl"
},
{
"type": "WEB",
"url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/jruby-openssl/CVE-2025-46551.yml"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P",
"type": "CVSS_V4"
}
],
"summary": "JRuby-OpenSSL has hostname verification disabled by default"
}
GHSA-76QH-XR7Q-H39M
Vulnerability from github – Published: 2026-06-04 18:30 – Updated: 2026-07-15 22:30An issue was discovered in OpenStack oslo.messaging 1.0.0 through 17.3.0. The oslo.messaging RabbitMQ driver does not perform TLS hostname verification when connecting to the message broker. When ssl_ca_file is configured, the driver enables certificate chain validation but does not pass the expected broker hostname into the underlying TLS stack. Any certificate signed by the deployment CA is accepted regardless of hostname, allowing an attacker who can intercept control-plane traffic to impersonate the RabbitMQ broker and perform a man-in-the-middle attack on RPC and notification traffic. All OpenStack services using oslo.messaging with RabbitMQ over TLS are affected.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "oslo.messaging"
},
"ranges": [
{
"events": [
{
"introduced": "1.0.0"
},
{
"last_affected": "17.3.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-44393"
],
"database_specific": {
"cwe_ids": [
"CWE-295",
"CWE-297"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-15T22:30:07Z",
"nvd_published_at": "2026-06-04T16:16:38Z",
"severity": "HIGH"
},
"details": "An issue was discovered in OpenStack oslo.messaging 1.0.0 through 17.3.0. The oslo.messaging RabbitMQ driver does not perform TLS hostname verification when connecting to the message broker. When ssl_ca_file is configured, the driver enables certificate chain validation but does not pass the expected broker hostname into the underlying TLS stack. Any certificate signed by the deployment CA is accepted regardless of hostname, allowing an attacker who can intercept control-plane traffic to impersonate the RabbitMQ broker and perform a man-in-the-middle attack on RPC and notification traffic. All OpenStack services using oslo.messaging with RabbitMQ over TLS are affected.",
"id": "GHSA-76qh-xr7q-h39m",
"modified": "2026-07-15T22:30:07Z",
"published": "2026-06-04T18:30:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44393"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2026-44393"
},
{
"type": "WEB",
"url": "https://bugs.launchpad.net/oslo.messaging/+bug/2150316"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2484835"
},
{
"type": "PACKAGE",
"url": "https://github.com/openstack/oslo.messaging"
},
{
"type": "WEB",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44393.json"
},
{
"type": "WEB",
"url": "https://wiki.openstack.org/wiki/OSSN/OSSN-0096"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "OpenStack oslo.messaging does not verify RabbitMQ broker hostname during TLS handshake"
}
GHSA-7J7J-66CV-M239
Vulnerability from github – Published: 2024-04-25 18:31 – Updated: 2024-11-18 16:26Impact
ZITADEL provides users the possibility to use Time-based One-Time-Password (TOTP) and One-Time-Password (OTP) through SMS and Email.
While ZITADEL already gives administrators the option to define a Lockout Policy with a maximum amount of failed password check attempts, there was no such mechanism for (T)OTP checks.
Patches
2.x versions are fixed on >= 2.50.0
Workarounds
There is no workaround since a patch is already available.
References
None
Questions
If you have any questions or comments about this advisory, please email us at security@zitadel.com
Credits
Thanks to Jack Moran from Layer 9 Information Security, Ethan from zxsecurity and Amit Laish from GE Vernova for finding and reporting the vulnerability.
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/zitadel/zitadel"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.50.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-32868"
],
"database_specific": {
"cwe_ids": [
"CWE-287",
"CWE-297",
"CWE-307"
],
"github_reviewed": true,
"github_reviewed_at": "2024-04-25T18:31:31Z",
"nvd_published_at": "2024-04-26T00:15:08Z",
"severity": "HIGH"
},
"details": "### Impact\nZITADEL provides users the possibility to use Time-based One-Time-Password (TOTP) and One-Time-Password (OTP) through SMS and Email.\n\nWhile ZITADEL already gives administrators the option to define a `Lockout Policy` with a maximum amount of failed password check attempts, there was no such mechanism for (T)OTP checks.\n\n### Patches\n2.x versions are fixed on \u003e= [2.50.0](https://github.com/zitadel/zitadel/releases/tag/v2.50.0)\n\n### Workarounds\nThere is no workaround since a patch is already available.\n\n### References\nNone\n\n### Questions\nIf you have any questions or comments about this advisory, please email us at [security@zitadel.com](mailto:security@zitadel.com)\n\n### Credits\n\nThanks to Jack Moran from Layer 9 Information Security, Ethan from zxsecurity and Amit Laish from GE Vernova for finding and reporting the vulnerability. \n",
"id": "GHSA-7j7j-66cv-m239",
"modified": "2024-11-18T16:26:40Z",
"published": "2024-04-25T18:31:31Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/zitadel/zitadel/security/advisories/GHSA-7j7j-66cv-m239"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-32868"
},
{
"type": "PACKAGE",
"url": "https://github.com/zitadel/zitadel"
},
{
"type": "WEB",
"url": "https://github.com/zitadel/zitadel/releases/tag/v2.50.0"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "ZITADEL\u0027s Improper Lockout Mechanism Leads to MFA Bypass"
}
GHSA-7JWG-HQ85-C6M6
Vulnerability from github – Published: 2022-09-22 00:00 – Updated: 2022-12-06 19:50Jenkins SmallTest Plugin 1.0.4 and earlier does not perform hostname validation when connecting to the configured View26 server that could be abused using a man-in-the-middle attack to intercept these connections. There is currently no known workaround or fix for this issue.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "com.smalltest:smalltest"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "1.0.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2022-41243"
],
"database_specific": {
"cwe_ids": [
"CWE-297"
],
"github_reviewed": true,
"github_reviewed_at": "2022-09-23T13:31:37Z",
"nvd_published_at": "2022-09-21T16:15:00Z",
"severity": "MODERATE"
},
"details": "Jenkins SmallTest Plugin 1.0.4 and earlier does not perform hostname validation when connecting to the configured View26 server that could be abused using a man-in-the-middle attack to intercept these connections. There is currently no known workaround or fix for this issue.",
"id": "GHSA-7jwg-hq85-c6m6",
"modified": "2022-12-06T19:50:46Z",
"published": "2022-09-22T00:00:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-41243"
},
{
"type": "PACKAGE",
"url": "https://github.com/jenkinsci/smalltest-plugin"
},
{
"type": "WEB",
"url": "https://www.jenkins.io/security/advisory/2022-09-21/#SECURITY-2068"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Jenkins SmallTest Plugin missing hostname validation"
}
GHSA-7MC8-G97X-QG4J
Vulnerability from github – Published: 2026-09-08 18:32 – Updated: 2026-09-08 18:32A improper validation of certificate with host mismatch vulnerability in Fortinet FortiOS 7.6.1 through 7.6.6, FortiProxy 7.6.2 through 7.6.6 may allow attacker to information disclosure via
{
"affected": [],
"aliases": [
"CVE-2026-84393"
],
"database_specific": {
"cwe_ids": [
"CWE-297"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-08T17:18:37Z",
"severity": "HIGH"
},
"details": "A improper validation of certificate with host mismatch vulnerability in Fortinet FortiOS 7.6.1 through 7.6.6, FortiProxy 7.6.2 through 7.6.6 may allow attacker to information disclosure via \u003cinsert attack vector here\u003e",
"id": "GHSA-7mc8-g97x-qg4j",
"modified": "2026-09-08T18:32:02Z",
"published": "2026-09-08T18:32:02Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84393"
},
{
"type": "WEB",
"url": "https://fortiguard.fortinet.com/psirt/FG-IR-26-174"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-7PWC-H2J2-RJGJ
Vulnerability from github – Published: 2026-05-05 09:31 – Updated: 2026-06-02 22:10Improper Validation of Certificate with Host Mismatch vulnerability in Apache Thrift.
This issue affects Apache Thrift: before 0.23.0.
Users are recommended to upgrade to version 0.23.0, which fixes the issue.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 0.22.0"
},
"package": {
"ecosystem": "Maven",
"name": "org.apache.thrift:libthrift"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.23.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-43869"
],
"database_specific": {
"cwe_ids": [
"CWE-297"
],
"github_reviewed": true,
"github_reviewed_at": "2026-05-08T19:19:58Z",
"nvd_published_at": "2026-05-05T08:16:01Z",
"severity": "HIGH"
},
"details": "Improper Validation of Certificate with Host Mismatch vulnerability in Apache Thrift.\n\nThis issue affects Apache Thrift: before 0.23.0.\n\nUsers are recommended to upgrade to version [0.23.0](https://github.com/apache/thrift/releases/tag/v0.23.0), which fixes the issue.",
"id": "GHSA-7pwc-h2j2-rjgj",
"modified": "2026-06-02T22:10:43Z",
"published": "2026-05-05T09:31:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43869"
},
{
"type": "WEB",
"url": "https://github.com/apache/thrift/commit/0919c3d5506151514e283a63e1fe1ce83e2449d8"
},
{
"type": "PACKAGE",
"url": "https://github.com/apache/thrift"
},
{
"type": "WEB",
"url": "https://github.com/apache/thrift/releases/tag/v0.23.0"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread/3hsgl1b69wzq3ry39scqbv2dhyl3j52r"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/05/05/3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
}
],
"summary": "Apache Thrift has an Improper Validation of Certificate with Host Mismatch Vulnerability"
}
GHSA-7Q9P-CX8R-RH2Q
Vulnerability from github – Published: 2026-01-08 12:30 – Updated: 2026-01-08 15:31When doing SSH-based transfers using either SCP or SFTP, and setting the known_hosts file, libcurl could still mistakenly accept connecting to hosts not present in the specified file if they were added as recognized in the libssh global known_hosts file.
{
"affected": [],
"aliases": [
"CVE-2025-15079"
],
"database_specific": {
"cwe_ids": [
"CWE-297"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-01-08T10:15:47Z",
"severity": "MODERATE"
},
"details": "When doing SSH-based transfers using either SCP or SFTP, and setting the\nknown_hosts file, libcurl could still mistakenly accept connecting to hosts\n*not present* in the specified file if they were added as recognized in the\nlibssh *global* known_hosts file.",
"id": "GHSA-7q9p-cx8r-rh2q",
"modified": "2026-01-08T15:31:25Z",
"published": "2026-01-08T12:30:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-15079"
},
{
"type": "WEB",
"url": "https://hackerone.com/reports/3477116"
},
{
"type": "WEB",
"url": "https://curl.se/docs/CVE-2025-15079.html"
},
{
"type": "WEB",
"url": "https://curl.se/docs/CVE-2025-15079.json"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/01/07/6"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-7VW7-RJFX-QMP5
Vulnerability from github – Published: 2026-09-03 21:31 – Updated: 2026-09-03 21:31IBM Netezza Software 11.3.0.3 through Interim Fix 002 does not validate or improperly validates TLS certificate validation, which could allow an attacker to obtain sensitive information using man in the middle techniques.
{
"affected": [],
"aliases": [
"CVE-2026-9744"
],
"database_specific": {
"cwe_ids": [
"CWE-297"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-03T21:17:24Z",
"severity": "MODERATE"
},
"details": "IBM Netezza Software 11.3.0.3 through Interim Fix 002 does not validate or improperly validates TLS certificate validation, which could allow an attacker to obtain sensitive information using man in the middle techniques.",
"id": "GHSA-7vw7-rjfx-qmp5",
"modified": "2026-09-03T21:31:17Z",
"published": "2026-09-03T21:31:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9744"
},
{
"type": "WEB",
"url": "https://www.ibm.com/support/pages/node/7284359"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-7XRH-HQFC-G7QR
Vulnerability from github – Published: 2026-03-07 09:30 – Updated: 2026-03-10 19:32Hostname verification in Apache ZooKeeper ZKTrustManager falls back to reverse DNS (PTR) when IP SAN validation fails, allowing attackers who control or spoof PTR records to impersonate ZooKeeper servers or clients with a valid certificate for the PTR name. It's important to note that attacker must present a certificate which is trusted by ZKTrustManager which makes the attack vector harder to exploit. Users are recommended to upgrade to version 3.8.6 or 3.9.5, which fixes this issue by introducing a new configuration option to disable reverse DNS lookup in client and quorum protocols.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.zookeeper:zookeeper"
},
"ranges": [
{
"events": [
{
"introduced": "3.8.0"
},
{
"fixed": "3.8.6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.zookeeper:zookeeper"
},
"ranges": [
{
"events": [
{
"introduced": "3.9.0"
},
{
"fixed": "3.9.5"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-24281"
],
"database_specific": {
"cwe_ids": [
"CWE-295",
"CWE-297"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-10T19:32:52Z",
"nvd_published_at": "2026-03-07T09:16:07Z",
"severity": "HIGH"
},
"details": "Hostname verification in Apache ZooKeeper ZKTrustManager falls back to reverse DNS (PTR) when IP SAN validation fails, allowing attackers who control or spoof PTR records to impersonate ZooKeeper servers or clients with a valid certificate for the PTR name. It\u0027s important to note that attacker must present a certificate which is trusted by ZKTrustManager which makes the attack vector harder to exploit. Users are recommended to upgrade to version 3.8.6 or 3.9.5, which fixes this issue by introducing a new configuration option to disable reverse DNS lookup in client and quorum protocols.",
"id": "GHSA-7xrh-hqfc-g7qr",
"modified": "2026-03-10T19:32:52Z",
"published": "2026-03-07T09:30:15Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-24281"
},
{
"type": "WEB",
"url": "https://github.com/apache/zookeeper/commit/66c4efecdda1302d9cfb3af9eedb122b74452bf3"
},
{
"type": "PACKAGE",
"url": "https://github.com/apache/zookeeper"
},
{
"type": "WEB",
"url": "https://issues.apache.org/jira/browse/ZOOKEEPER-4986"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread/088ddsbrzhd5lxzbqf5n24yg0mwh9jt2"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/03/07/4"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Apache ZooKeeper: Reverse-DNS fallback enables hostname verification bypass in ZooKeeper ZKTrustManager"
}
GHSA-85RW-G4F4-JPRR
Vulnerability from github – Published: 2026-06-01 09:31 – Updated: 2026-07-07 23:46It was identified that the LDAP client implementation in version 2.1.7 does not verify if the server certificate matches the intended LDAP hostname. While the underlying code validates the certificate chain against a trusted authority, the absence of endpoint identification allows a valid certificate issued for an entirely unrelated host to be improperly accepted. This oversight leaves the connection highly vulnerable to server impersonation and complete connection compromise.
The root cause of this vulnerability lies in the incomplete TLS server identity verification within the LDAP client implementation.
The attacker requires MITM capability on the network to exploit this vulnerability. This attacker must be able to present a certificate trusted by the client's configured trust store.
The hostname verification has been enforced in the new version of the LDAP API.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.directory.api:api-ldap-client-api"
},
"ranges": [
{
"events": [
{
"introduced": "2.0.0"
},
{
"fixed": "2.1.8"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-35563"
],
"database_specific": {
"cwe_ids": [
"CWE-297"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-07T23:46:48Z",
"nvd_published_at": "2026-06-01T08:16:20Z",
"severity": "HIGH"
},
"details": "It was identified that the LDAP client implementation in version 2.1.7 does not verify if the server certificate matches the intended LDAP hostname. While the underlying code validates the certificate chain against a trusted authority, the absence of endpoint identification allows a valid certificate issued for an entirely unrelated host to be improperly accepted. This oversight leaves the connection highly vulnerable to server impersonation and complete connection compromise.\n\nThe root cause of this vulnerability lies in the incomplete TLS server identity verification within the LDAP client implementation.\n\nThe attacker requires MITM capability on the network to exploit this vulnerability. This attacker must be able to present a certificate trusted by the client\u0027s configured trust store.\n\nThe hostname verification has been enforced in the new version of the LDAP API.",
"id": "GHSA-85rw-g4f4-jprr",
"modified": "2026-07-07T23:46:48Z",
"published": "2026-06-01T09:31:11Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35563"
},
{
"type": "WEB",
"url": "https://github.com/apache/directory-ldap-api/commit/57a7726d8b6436c74945c12f5ba4e12d232d2bac"
},
{
"type": "PACKAGE",
"url": "https://github.com/apache/directory-ldap-api"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread/5rc2nzqxp1m9wknyf93r8dnp46fhc1nn"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/06/01/2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:L/SA:L",
"type": "CVSS_V4"
}
],
"summary": "Apache Directory LDAP API lacks server certificate verification for LDAP hostnames"
}
Mitigation
Fully check the hostname of the certificate and provide the user with adequate information about the nature of the problem and how to proceed.
Mitigation
If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
No CAPEC attack patterns related to this CWE.