CVE-2021-30027

medium

Published — · Modified —

CVSS v3

—

CVSS v2

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VIR risk

5.5

Description

md_analyze_line in md4c.c in md4c 0.4.7 allows attackers to trigger use of uninitialized memory, and cause a denial of service via a malformed Markdown document.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-30027

OS impact

OS	Version	Status	Fixed in
arch		fixed	`0.4.8-1`
debian	bookworm	fixed	`0.4.7-2`
debian	bullseye	fixed	`0.4.7-2`
debian	forky	fixed	`0.4.7-2`
debian	sid	fixed	`0.4.7-2`
debian	trixie	fixed	`0.4.7-2`

References

https://security-tracker.debian.org/tracker/CVE-2021-30027

Verify integrity in audit chain (admin only). AS-IS.