Out-of-Bounds Write in Gnu Apache (CVE-2017-6891)
Summary
Out-of-bounds write in Gnu Apache (CVE-2017-6891). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
Two errors in the "asn1_find_node()" function (lib/parser_aux.c) within GnuTLS libtasn1 version 4.10 can be exploited to cause a stacked-based buffer overflow by tricking a user into processing a specially crafted assignments file via the e.g. asn1Coding utility.
Source: NIST National Vulnerability Database NVD
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-2017-6891 has been found in Gnu Apache.
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 "Gnu Apache CVE-2017-6891" on the vendor's site.
CVE-2017-6891 (Gnu Apache) — CWE-787 / CVSS v3 8.8
Attack vector: remote (network-reachable) / 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 write (CWE-787) exists in Gnu Apache.
Check the vendor advisory for the affected versions of Gnu Apache.
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. Run grep -r 'Apache' . 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 'Apache' . | 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
Apache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-2017-6891 libtasn1 Fixed in: 4.7-r2
- Debian DEBIAN-CVE-2017-6891 libtasn1-6 Fixed in: 4.10-1.1
References
- advisory debian.org
- advisory securityfocus.com
- advisory securitytracker.com
- advisory security.gentoo.org
- patch secuniaresearch.flexerasoftware.com
- report secuniaresearch.flexerasoftware.com
- web git.savannah.gnu.org
- web lists.opensuse.org
- web lists.apache.org
- web lists.apache.org