Vulnerability in source-map-js (CVE-2026-93749)
Summary
Vulnerability in source-map-js (CVE-2026-93749). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 1.2.2 or later.
Original description
The description as published by the source.
source-map-js through 1.2.1 fails to validate the per-section offset line value in indexed source maps, allowing attackers to specify arbitrary numeric values. Attackers can supply extremely large offset line values that cause synchronous event loop blocking for extended periods, preventing the service from handling other requests.
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-2026-93749 has been found in source-map-js.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: upgrade source-map-js to 1.2.2 or later.
If unsure, ask your IT team or search "source-map-js CVE-2026-93749" on the vendor's site.
CVE-2026-93749 (source-map-js) — CWE-1284 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 1.2.2 — 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 (CWE-1284) exists in source-map-js.
Check the vendor advisory for the affected versions of source-map-js.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to 1.2.2.
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 'source-map-js' . 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
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1Identify exposure identify
grep -r 'source-map-js' . | 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
source-map-jsを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade source-map-js to 1.2.2ステージング環境で 1.2.2 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。
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3Post-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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-93749 node-postcss
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web vulncheck.com
- web github.com
- web github.com
- web github.com
- web github.com