Affected: Homebrew: ansible

### Summary

`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.

### Details

Affected function: `ldap.dn.escape_dn_chars(s)`

File: Lib/ldap/dn.py

Buggy behavior: For NUL, the function does:

`s = s.replace('\000', '\\\000') # backslash + literal NUL`

This produces Python strings which, when passed to python-ldap APIs (e.g., `add_s`, `modify_s`, r`ename_s`, or used as search bases), contain an embedded NUL. python-ldap then raises ValueError: embedded null character (or otherwise fails) before any network I/O. With correct RFC-4514 encoding (`\00`), the client proceeds and the server can apply its own syntax rules (e.g., AD will reject NUL in CN with result: 34), proving the failure originates in the escaping helper.

Why it matters: Projects follow the docs which state this function “should be used when building LDAP DN strings from arbitrary input.” The function’s guarantee is therefore relied upon as a safety API. A single NUL in attacker-controlled input reliably breaks client workflows (crash/unhandled exception, stuck retries, poison queue record), i.e., a DoS.

Standards: RFC 4514 requires special characters and controls to be escaped using hex form; a li…

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: PyPI: python-ldap

### Summary

`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.

### Details

Affected function: `ldap.dn.escape_dn_chars(s)`

File: Lib/ldap/dn.py

Buggy behavior: For NUL, the function does:

`s = s.replace('\000', '\\\000') # backslash + literal NUL`

This produces Python strings which, when passed to python-ldap APIs (e.g., `add_s`, `modify_s`, r`ename_s`, or used as search bases), contain an embedded NUL. python-ldap then raises ValueError: embedded null character (or otherwise fails) before any network I/O. With correct RFC-4514 encoding (`\00`), the client proceeds and the server can apply its own syntax rules (e.g., AD will reject NUL in CN with result: 34), proving the failure originates in the escaping helper.

Why it matters: Projects follow the docs which state this function “should be used when building LDAP DN strings from arbitrary input.” The function’s guarantee is therefore relied upon as a safety API. A single NUL in attacker-controlled input reliably breaks client workflows (crash/unhandled exception, stuck retries, poison queue record), i.e., a DoS.

Standards: RFC 4514 requires special characters and controls to be escaped using hex form; a li…

Affected: openEuler:22.03-LTS-SP4: python-ldap

python-ldap: python-ldap provides an object-oriented API to access LDAP directory servers from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose. Additionally the package contains modules for other LDAP-related stuff (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations and controls, etc.). Security Fix(es):

python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, the sanitization method `ldap.filter.escape_filter_chars` can be tricked to skip escaping of special characters when a crafted `list` or `dict` is supplied as the `assertion_value` parameter, and the non-default `escape_mode=1` is configured. The method `ldap.filter.escape_filter_chars` supports 3 different escaping modes. `escape_mode=0` (default) and `escape_mode=2` happen to raise exceptions when a `list` or `dict` object is supplied as the `assertion_value` parameter. However, `escape_mode=1` computes without performing adequate logic to ensure a fully escaped return value. If an application relies on the vulnerable method in the `python-ldap` library to escape untrusted user input, an attacker might be able to abuse the vulnerability to launch ldap injection attacks which could potentially disclose or manipulate ldap data meant to be inaccessible to them. Version 3.4.5 fixes the issue by adding a type check at the start of the `ldap.filter.escape_filter_chars` method to raise an exception when the s…

python311-ldap-3.4.5-1.1 on GA media

Affected: PyPI: python-ldap

### Summary

`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.

### Details

Affected function: `ldap.dn.escape_dn_chars(s)`

File: Lib/ldap/dn.py

Buggy behavior: For NUL, the function does:

`s = s.replace('\000', '\\\000') # backslash + literal NUL`

This produces Python strings which, when passed to python-ldap APIs (e.g., `add_s`, `modify_s`, r`ename_s`, or used as search bases), contain an embedded NUL. python-ldap then raises ValueError: embedded null character (or otherwise fails) before any network I/O. With correct RFC-4514 encoding (`\00`), the client proceeds and the server can apply its own syntax rules (e.g., AD will reject NUL in CN with result: 34), proving the failure originates in the escaping helper.

Why it matters: Projects follow the docs which state this function “should be used when building LDAP DN strings from arbitrary input.” The function’s guarantee is therefore relied upon as a safety API. A single NUL in attacker-controlled input reliably breaks client workflows (crash/unhandled exception, stuck retries, poison queue record), i.e., a DoS.

Standards: RFC 4514 requires special characters and controls to be escaped using hex form; a li…

Security update for python-ldap

Affected: Ubuntu:Pro:16.04:LTS: python-ldap, Ubuntu:Pro:18.04:LTS: python-ldap, Ubuntu:Pro:20.04:LTS: python-ldap, Ubuntu:22.04:LTS: python-ldap, Ubuntu:24.04:LTS: python-ldap, Ubuntu:25.10: python-ldap

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.

Ein Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.