USN-8581-1: libarchive vulnerabilities
It was discovered that libarchive did not properly manage memory when unpacking certain RAR5 archives, leading to a double free. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-14164) It was discovered that libarchive did not properly validate certain tar archives, leading to a buffer overflow. A remote attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-15028) It was discovered that libarchive did not properly validate certain malformed ACL entries. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-5745)
CSIRTS triage
- What
- Multiple vulnerabilities exist that can lead to denial of service or arbitrary code execution.
- Who is affected
- Users of libarchive on Ubuntu 26.04 LTS.
- Urgency
- Remediation is important due to the potential for denial of service and code execution.
- Action
- Update libarchive to the latest version to address these vulnerabilities.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://ubuntu.com/security/notices/USN-8581-1
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-141640.35% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 28% of all scored CVEs.
- Low exploitation riskCVE-2026-150280.20% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 10% of all scored CVEs.
- Low exploitation riskCVE-2026-57450.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-14164 | coverage & exploitation status | NVD · CVE.org |
| CVE-2026-15028 | coverage & exploitation status | NVD · CVE.org |
| CVE-2026-5745 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- medium[UPDATE] [medium] libarchive: Vulnerability allows denial of servicecert-bund
- low[NEW] [low] libarchive: Vulnerability allows code execution and DoScert-bund
- lowCVE-2026-15028: Libarchive: heap overflow oob read while parsing a tar archive contains a pax extended headermsrc
- lowCVE-2026-15028: A flaw was found in libarchive. This vulnerability allows a remote attacker to trigger a heap …nvd
- unknownMultiple vulnerabilities in Microsoft Azure Linux (July 10, 2026)cert-fr-avis
- highCVE-2026-14164: A double free issue has been identified in libarchive's RAR5 reader. During parsing of a speci…nvd
- highCVE-2026-14164: Libarchive: double-free vulnerability in rar5 decompression logic via dangling filtered_buf po…msrc
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