CVE-2021-46823

Name: CVE-2021-46823
Creator: NVD / NIST
Published: 2022-06-18T16:15:08.173+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.70%

Last modified Jun 17, 2026

CVE-2021-46823 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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.. EPSS estimates a 1.70% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

1.70%

74.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-1333

Affected Software

Vendor	Product	Versions
Python-Ldap	Python-Ldap	< 3.4.0

References

https://exchange.xforce.ibmcloud.com/vulnerabilities/221507Third Party Advisory, VDB Entry
https://github.com/python-ldap/python-ldap/security/advisories/GHSA-r8wq-qrxc-hmcmThird Party Advisory
https://exchange.xforce.ibmcloud.com/vulnerabilities/221507Third Party Advisory, VDB Entry
https://github.com/python-ldap/python-ldap/security/advisories/GHSA-r8wq-qrxc-hmcmThird Party Advisory

Timeline

Published: Jun 18, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-46823?

How severe is CVE-2021-46823?

CVE-2021-46823 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.70% probability of exploitation in the next 30 days.

How do I fix CVE-2021-46823?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-46823?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST