Microsoft security update for CVE-2026-18477 — azl3 tar
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-18477. This page also shows what EchelonGraph holds for CVE-2026-18477, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products2
- azl3 tar 1.35-2 on Azure Linux 3.0
- azl3 tar 1.35-3 on Azure Linux 3.0
✅ Updates Microsoft lists: 2 updates
2 rows: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | — |
| — | Security Update | — |
🧭 EchelonGraph on CVE-2026-18477
- EchelonGraph score
- 4.4 MEDIUM
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
A TOCTOU (Time-of-Check Time-of-Use) vulnerability in GNU tar's incremental dumpdir 'X' rename handling allows a local attacker with write access to a directory being backed up to influence the restore process if the attacker has access to the system where the restore is being performed. During restoration, files or directories may be created, renamed or overwritten outside the intended extraction directory. This could lead to unauthorized file modification or, in some cases, privilege escalation. Exploitation does not require the attacker to modify or craft the archive, and standard backup and restore workflows—including extracting into a newly created directory without using the -P option do not mitigate the issue.
Published by Red Hat, Inc., the CVE Numbering Authority that assigned CVE-2026-18477, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).