Vulnerability in tar
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as UBUNTU-CVE-2026-5704 has been found in tar.
Data can be tampered with by attackers.
What to do: upgrade tar to 1.27.1-1ubuntu0.1+esm7 or later.
If unsure, ask your IT team or search "tar UBUNTU-CVE-2026-5704" on the vendor's site.
UBUNTU-CVE-2026-5704 (tar)
Attack vector: local
Patched: 1.27.1-1ubuntu0.1+esm7 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in tar.
Check the vendor advisory for the affected versions of tar.
Severity: ?. Data can be tampered with by attackers.
Update to 1.27.1-1ubuntu0.1+esm7.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'tar' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1
Identify exposureidentify
grep -r 'tar' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
tarを grep し、稼働しているサービス・バージョンを把握する。 -
2
Apply patchpatch
Upgrade tar to 1.27.1-1ubuntu0.1+esm7ステージング環境で 1.27.1-1ubuntu0.1+esm7 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3
Post-deployment verificationverify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
| Package | Affected → Fixed | |
|---|---|---|
| Ubuntu:Pro:14.04:LTStar |
< 1.27.1-1ubuntu0.1+esm7→ 1.27.1-1ubuntu0.1+esm7 |
1.27.1-1ubuntu0.1+esm7 |
| Ubuntu:Pro:16.04:LTStar |
< 1.28-2.1ubuntu0.2+esm6→ 1.28-2.1ubuntu0.2+esm6 |
1.28-2.1ubuntu0.2+esm6 |
| Ubuntu:Pro:18.04:LTStar |
< 1.29b-2ubuntu0.4+esm4→ 1.29b-2ubuntu0.4+esm4 |
1.29b-2ubuntu0.4+esm4 |
| Ubuntu:20.04:LTStar |
All versions→ Not listed |
Not listed |
| Ubuntu:22.04:LTStar |
< 1.34+dfsg-1ubuntu0.1.22.04.6→ 1.34+dfsg-1ubuntu0.1.22.04.6 |
1.34+dfsg-1ubuntu0.1.22.04.6 |
| Ubuntu:24.04:LTStar |
< 1.35+dfsg-3ubuntu0.4→ 1.35+dfsg-3ubuntu0.4 |
1.35+dfsg-3ubuntu0.4 |
| Ubuntu:25.10tar |
All versions→ Not listed |
Not listed |
| Ubuntu:26.04:LTStar |
< 1.35+dfsg-4ubuntu0.4→ 1.35+dfsg-4ubuntu0.4 |
1.35+dfsg-4ubuntu0.4 |
| Ubuntu:Pro:20.04:LTStar |
< 1.30+dfsg-7ubuntu0.20.04.4+esm3→ 1.30+dfsg-7ubuntu0.20.04.4+esm3 |
1.30+dfsg-7ubuntu0.20.04.4+esm3 |
Original description The description as published by the source.
A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection.
Source: OSV.dev (Open Source Vulnerabilities) OSV
References
- advisory ubuntu.com
- advisory ubuntu.com
- advisory ubuntu.com
- report ubuntu.com
- report cve.org
- report access.redhat.com