Vulnerability in md4c
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 DEBIAN-CVE-2020-26148 has been found in md4c.
Risk of unauthorized operations or information disclosure.
What to do: upgrade md4c to 0.4.5-2 or later.
If unsure, ask your IT team or search "md4c DEBIAN-CVE-2020-26148" on the vendor's site.
DEBIAN-CVE-2020-26148 (md4c)
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 0.4.5-2 — 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 (unclassified) exists in md4c.
Check the vendor advisory for the affected versions of md4c.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 0.4.5-2.
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 'md4c' . 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
-
1
Identify exposureidentify
grep -r 'md4c' . | 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
md4cを grep し、稼働しているサービス・バージョンを把握する。 -
2
Apply patchpatch
Upgrade md4c to 0.4.5-2ステージング環境で 0.4.5-2 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。
-
3
Post-deployment verificationverify
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
| Ecosystem | Package | Affected | Fixed |
|---|---|---|---|
| Debian:12 | md4c |
< 0.4.5-2 |
0.4.5-2 |
| Debian:13 | md4c |
< 0.4.5-2 |
0.4.5-2 |
| Debian:14 | md4c |
< 0.4.5-2 |
0.4.5-2 |
Original description The description as published by the source.
md_push_block_bytes in md4c.c in md4c 0.4.5 allows attackers to trigger use of uninitialized memory, and cause a denial of service (e.g., assertion failure) via a malformed Markdown document.
Source: OSV.dev (Open Source Vulnerabilities) OSV
References
- advisory security-tracker.debian.org