CVE-2026-4111

Publication date 13 March 2026

Last updated 6 April 2026

Ubuntu priority

Cvss 3 Severity Score

Description

A flaw was identified in the RAR5 archive decompression logic of the libarchive library, specifically within the archive_read_data() processing path. When a specially crafted RAR5 archive is processed, the decompression routine may enter a state where internal logic prevents forward progress. This condition results in an infinite loop that continuously consumes CPU resources. Because the archive passes checksum validation and appears structurally valid, affected applications cannot detect the issue before processing. This can allow attackers to cause persistent denial-of-service conditions in services that automatically process archives.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libarchive	25.10 questing	Fixed 3.7.7-0ubuntu3.1
	24.04 LTS noble	Fixed 3.7.2-2ubuntu0.6
	22.04 LTS jammy	Fixed 3.6.0-1ubuntu1.6
	20.04 LTS focal	Fixed 3.4.0-2ubuntu1.5+esm1
	18.04 LTS bionic	Fixed 3.2.2-3.1ubuntu0.7+esm2
	16.04 LTS xenial	Fixed 3.1.2-11ubuntu0.16.04.8+esm2
	14.04 LTS trusty	Fixed 3.1.2-7ubuntu2.8+esm4

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Patch details

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

Package	Patch details
libarchive	Upstream: ec19fcb

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-8147-1
libarchive vulnerabilities
2 April 2026