CVE-2026-23490

Publication date 16 January 2026

Last updated 22 January 2026

Ubuntu priority

Cvss 3 Severity Score

Description

pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.2, a Denial-of-Service issue has been found that leads to memory exhaustion from malformed RELATIVE-OID with excessive continuation octets. This vulnerability is fixed in 0.6.2.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
pyasn1	25.10 questing	Fixed 0.6.1-1ubuntu0.1
	24.04 LTS noble	Fixed 0.4.8-4ubuntu0.1
	22.04 LTS jammy	Fixed 0.4.8-1ubuntu0.1
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Needs evaluation

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
pyasn1	Upstream: 3908f14

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-7975-1
pyasn1 vulnerability
22 January 2026