Out-of-Bounds Read in tar (CVE-2021-20193)
Summary
Vulnerability in tar (CVE-2021-20193). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A flaw was found in the src/list.c of tar 1.33 and earlier. This flaw allows an attacker who can submit a crafted input file to tar to cause uncontrolled consumption of memory. The highest threat from this vulnerability is to system availability.
Source: NIST National Vulnerability Database NVD GitHub Advisory
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 CVE-2021-20193 has been found in tar.
Risk of unauthorized operations or information disclosure. CVSS score: 3.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "tar CVE-2021-20193" on the vendor's site.
CVE-2021-20193 (tar) — CWE-125 / CVSS v3 3.3
Attack vector: local / unauthenticated
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.
Out-of-bounds read (CWE-125) exists in tar.
Check the vendor advisory for the affected versions of tar.
Severity: Low (CVSS 3.3/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
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
-
1Identify exposure identify
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。 -
2Post-deployment verification verify
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。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Alpine Linux ALPINE-CVE-2021-20193 tar Fixed in: 1.32-r1
- Debian DEBIAN-CVE-2021-20193 tar Fixed in: 1.34+dfsg-1
References
- advisory security.gentoo.org
- patch bugzilla.redhat.com
- patch git.savannah.gnu.org
- patch savannah.gnu.org
- web cert-portal.siemens.com
- web nvd.nist.gov
- web github.com