# CVE-2026-4424: Libarchive: libarchive: information disclosure via heap out-of-bounds read in rar archive processing

> A remote attacker can disclose sensitive heap memory by providing a specially crafted RAR archive to applications using Libarchive.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Mar 2026
- **Updated:** 14 Oct 2026
- **Also known as:** ALSA-2026:8492, AZL-80403, BELL-CVE-2026-4424, CLSA-2026-1776872469, CLSA-2026-1776873238, CLSA-2026-1780922803, CLSA-2026-1782303221, DEBIAN-CVE-2026-4424, ECHO-0051-e755-e08e, GHSA-c75f-55f6-f63q, MINI-8h29-vv6x-3j32, RHSA-2026:8492, RLSA-2026:8492, UBUNTU-CVE-2026-4424

## What is CVE-2026-4424?

CVE-2026-4424 is a high-severity vulnerability in Libarchive Libarchive, published on 19 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in libarchive. This heap out-of-bounds read vulnerability exists in the RAR archive processing logic due to improper validation of the LZSS sliding window size after transitions between compression methods. A remote attacker can exploit this by providing a specially crafted RAR archive, leading to the disclosure of sensitive heap memory information without requiring authentication or user interaction.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-4424?

It affects 7 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `bsdtar` | AlmaLinux:10 | All versions | 3.7.7-8.el10_1 |
| `libarchive` | AlmaLinux:10 | All versions | 3.7.7-8.el10_1 |
| `libarchive-devel` | AlmaLinux:10 | All versions | 3.7.7-8.el10_1 |
| `bsdcat-debuginfo` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `bsdcpio-debuginfo` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `bsdtar` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `bsdtar-debuginfo` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `bsdunzip-debuginfo` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `libarchive` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `libarchive-debuginfo` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `libarchive-debugsource` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `libarchive-devel` | Red Hat:enterprise_linux:10.1 | All versions | 0:3.7.7-8.el10_1 |
| `libarchive` | Rocky Linux:10 | All versions | 0:3.7.7-8.el10_1 |

Products: Libarchive Libarchive, Redhat Enterprise Linux, Redhat Enterprise Linux Server Aus, Redhat Hardened Images, Redhat Openshift Container Platform, Redhat Openshift Container Platform for Arm64, Redhat Openshift Container Platform for Power.

## How do I fix CVE-2026-4424?

Apply the vendor's patch.

## Is CVE-2026-4424 being exploited?

There is no known exploitation of CVE-2026-4424 in the wild and no public exploit code.

## Other vulnerabilities in Libarchive Libarchive

- [CVE-2024-37407](https://insights.sbomify.com/CVE-2024-37407/): Memory corruption in n/a (critical 9.1)
- [CVE-2016-1541](https://insights.sbomify.com/CVE-2016-1541/): Memory corruption in n/a (high 8.8)
- [CVE-2016-6250](https://insights.sbomify.com/CVE-2016-6250/): Integer overflow in n/a (high 8.6)
- [CVE-2025-5914](https://insights.sbomify.com/CVE-2025-5914/): Libarchive: double free at archive_read_format_rar_seek_data() in archive_read_support_format_rar.c (high 7.8)
- [CVE-2024-48957](https://insights.sbomify.com/CVE-2024-48957/): Memory corruption in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4424 and fix it if it is affected.

What it is: CVE-2026-4424 is a high-severity vulnerability in Libarchive Libarchive, published on 19 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-4424 in the wild and no public exploit code.

Affected product: Libarchive Libarchive. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-4424/ (Markdown: https://insights.sbomify.com/CVE-2026-4424/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4424
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4424
- OSV: https://osv.dev/vulnerability/CVE-2026-4424

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-4424/
Summaries are generated and may contain mistakes; the official description above is the record.