---
title: CVE-2026-4111
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2026-4111
---

# CVE-2026-4111

Publication date 13 March 2026

Last updated 6 April 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2026-4111#impact-score)

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## 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  Ubuntu Pro |
| 18.04 LTS bionic | Fixed 3.2.2-3.1ubuntu0.7+esm2  Ubuntu Pro |
| 16.04 LTS xenial | Fixed 3.1.2-11ubuntu0.16.04.8+esm2  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 3.1.2-7ubuntu2.8+esm4  Ubuntu Pro |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2026-4111#patch-details)

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### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| libarchive | * Upstream:   [ec19fcb](https://github.com/libarchive/libarchive/commit/ec19fcbd20b18bd3b0fdcf2b3fb97789cd1bf575) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | None |
  | Integrity impact | None |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-4111)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-4111)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-4111)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-4111)

### Related Ubuntu Security Notices (USN)

+ [USN-8147-1](https://usn.ubuntu.com/USN-8147-1)
+ libarchive vulnerabilities
+ 2 April 2026

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-4111>
* <https://github.com/libarchive/libarchive/pull/2877>
* <https://access.redhat.com/security/cve/CVE-2026-4111>
* <https://bugzilla.redhat.com/show_bug.cgi?id=2446453>