Vulnerability in Siemens Libexpat Project (CVE-2021-45960)
Summary
Vulnerability in Siemens Libexpat Project (CVE-2021-45960). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory).
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
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-2021-45960 has been found in Siemens Libexpat Project.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Siemens Libexpat Project CVE-2021-45960" on the vendor's site.
CVE-2021-45960 (Siemens Libexpat Project) — CWE-682 / CVSS v3 8.8
Attack vector: remote (network-reachable) / no user interaction
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 (CWE-682) exists in Siemens Libexpat Project.
Check the vendor advisory for the affected versions of Siemens Libexpat Project.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
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. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Siemens Libexpat Project を使っているサービスとバージョンを洗い出す。
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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-2021-45960 expat Fixed in: 2.2.10-r0
- Debian DEBIAN-CVE-2021-45960 expat Fixed in: 2.4.3-1
- Ubuntu UBUNTU-CVE-2021-45960 expat Fixed in: 2.1.0-4ubuntu1.4+esm4
References
- advisory security.gentoo.org
- advisory security.netapp.com
- advisory tenable.com
- advisory bugzilla.mozilla.org
- advisory debian.org
- exploit github.com
- exploit openwall.com
- patch cert-portal.siemens.com
- patch github.com
- web nvd.nist.gov
- web security.netapp.com
- web cert-portal.siemens.com
- web cert-portal.siemens.com
- web github.com