Description
python-ldap before 3.4.0 is vulnerable to a denial of service when ldap.schema is used for untrusted schema definitions, because of a regular expression denial of service (ReDoS) flaw in the LDAP schema parser. By sending crafted regex input, a remote authenticated attacker could exploit this vulnerability to cause a denial of service condition.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | python-ldap | 3.4.0-1 | — |
| Debian 13 | python-ldap | 3.4.0-1 | — |
| Debian 12 | python-ldap | 3.4.0-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | python-ldap | 3.2.0-4ubuntu7.1 | USN-5508-1 |
| Ubuntu 20.04 LTS | python-ldap | 3.2.0-4ubuntu2.1 | USN-5508-1 |
| Ubuntu 18.04 LTS | python-ldap | 3.0.0-1ubuntu0.2 | USN-5508-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | python-ldap | 2.4.15-2.amzn2.0.3 | ALAS2-2024-2406 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | python-ldap | 3.4.0-1 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | python-ldap | < 3.4.0 | 3.4.0 | GHSA-qfr5-wjpw-q4c4 |
Advisories 3
- USN-5508-1 python-ldap vulnerability Ubuntu Security Notices (USN) · Feb 10, 2026
- ALAS2-2024-2406 Moderate: python-ldap security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jan 9, 2024
- WID-SEC-2023-0561 Xerox FreeFlow Print Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 18, 2023