#VU65120 Incorrect Regular Expression in python-ldap - CVE-2021-46823

Vulnerability identifier: #VU65120

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-46823

CWE-ID: CWE-185

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
python-ldap
Other software / Other software solutions

Vendor: python-ldap

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient input validation when processing regular expressions in the LDAP schema parser. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDos) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

python-ldap: 2.3.0 - 3.3.1

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External links
https://github.com/python-ldap/python-ldap/security/advisories/GHSA-r8wq-qrxc-hmcm

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.