CVE-2021-30027 json
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 malfor…
published 2021-04-29 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-16971
- cvss
- 5.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- md4c Debian 14, Debian 13, Debian 12 0.4.7-2
debian advisories DEBIAN-CVE-2021-30027
- md4c Arch Linux 0.4.8-1
arch linux advisories AVG-1895
- github.com/mity/md4c@4fc808d commit
Exploit prediction
0.70% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/mity/md4c/issues/155 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:N/A:P |
Classification
- Weakness
-
- CWE-908 Use of Uninitialized Resource
References
-
github.com
/mity/md4c/commit/4fc808d8fe8d8904f8525bb4231d854f45e23a19
patch, third-party-advisory
-
github.com
/mity/md4c/issues/155
exploit, issue-tracking, third-party-advisory
Sources
- CVE List CVE-2021-30027
- NVD CVE-2021-30027
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