CVE-2026-27171

Publication date 19 February 2026

Last updated 20 February 2026

Ubuntu priority

Cvss 3 Severity Score

Description

zlib before 1.3.2 allows CPU consumption via crc32_combine64 and crc32_combine_gen64 because x2nmodp can do right shifts within a loop that has no termination condition.

Read the notes from the security team

Why is this CVE low priority?

Resource consumption via API misuse only

Learn more about Ubuntu priority

Status

Show unmaintained releases

Package	Ubuntu Release	Status
zlib	25.10 questing	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Needs evaluation
rsync	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Vulnerable
	18.04 LTS bionic	Vulnerable
	16.04 LTS xenial	Vulnerable
	14.04 LTS trusty	Not affected
klibc	25.10 questing	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Needs evaluation
zsync	25.10 questing	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation

Notes

mdeslaur

since 3.2.0-1, rsync builds with the system zlib This issue stems from the misuse of an API, no indication that the API is being misused by anything in Ubuntu. This would only result in cpu consumption if it is in fact being misused. Marking this issue as low priority.

Severity score breakdown

Parameter	Value
Base score	2.9 · Low
Attack vector	Local
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	Low
Vector	CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L