Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS1yOHdxLXFyeGMtaG1jbc0YMg

ReDoS in LDAP schema parser

https://github.com/python-ldap/python-ldap/issues/424

Impact

The LDAP schema parser of python-ldap 3.3.1 and earlier are vulnerable to a regular expression denial-of-service attack. The issue affects clients that use ldap.schema package to parse LDAP schema definitions from an untrusted source.

Patches

The upcoming release of python-ldap 3.4.0 will contain a workaround to prevent ReDoS attacks. The schema parser refuses schema definitions with an excessive amount of backslashes.

Workarounds

As a workaround, users can check input for excessive amount of backslashes in schemas. More than a dozen backslashes per line are atypical.

References

CWE-1333

For more information

If you have any questions or comments about this advisory:

• Open an issue in python-ldap tracker

Permalink: https://github.com/advisories/GHSA-r8wq-qrxc-hmcm
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS1yOHdxLXFyeGMtaG1jbc0YMg
Source: GitHub Advisory Database
Origin: Unspecified
Severity: Moderate
Classification: General
Published: over 2 years ago
Updated: over 1 year ago

CVSS Score: 6.5
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Identifiers: GHSA-r8wq-qrxc-hmcm
References:

• https://github.com/python-ldap/python-ldap/security/advisories/GHSA-r8wq-qrxc-hmcm
• https://github.com/python-ldap/python-ldap/issues/424
• https://github.com/advisories/GHSA-r8wq-qrxc-hmcm

Repository: https://github.com/python-ldap/python-ldap
Blast Radius: 22.3

Affected Packages