Description
python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.
Affected products
python-ldap: python-ldap
References3
- github.com/python-ldap/python-ldap/commit/6ea80326a34ee60932196… Patch
- github.com/python-ldap/python-ldap/security/advisories/GHSA-p34… ExploitThird Party Advisory
- github.com/python-ldap/python-ldap/releases/tag/python-ldap-3.4… Release Notes
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
5.5
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 40 · as of 9 November 2026
- CWE
- CWE-116CWE-170
Could this be exploited in your environment?
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