Vulnerability in Firefox (CVE-2021-29993)
Summary
Vulnerability in Firefox (CVE-2021-29993). Data can be tampered with by attackers.
Original description
The description as published by the source.
Firefox for Android allowed navigations through the intent:// protocol, which could be used to cause crashes and UI spoofs. This bug only affects Firefox for Android. Other operating systems are unaffected.. This vulnerability affects Firefox < 92.
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-2021-29993 has been found in Firefox.
Data can be tampered with by attackers. CVSS score: 8.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Firefox CVE-2021-29993" on the vendor's site.
CVE-2021-29993 (Firefox) — CVSS v3 8.1
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.
A vulnerability (unclassified) exists in Firefox.
Check the vendor advisory for the affected versions of Firefox.
Severity: High (CVSS 8.1/10). Data can be tampered with by attackers.
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 'Firefox' . 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 'Firefox' . | 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
Firefox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。
References
- patch mozilla.org
- web bugzilla.mozilla.org
- web nvd.nist.gov
- web mozilla.org
- web github.com