CVE-2021-30027
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.
02 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.
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 0.69% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 52.5% of scored records. A rank, not a probability.
- NVD base score
- 5.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-04-29 14:29Z5 YR AGO
- Last updated
- 2024-08-03 22:24Z2 YR AGO
- Reserved
- 2021-04-02
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- CWE-908Use of Uninitialized ResourceBase
- Data version
- 5.1
- Document digest
- 2cec3bcf1b146d445e40a718da32586271b56d599134d293094b4cc302b8ea39
05 Affected products
06 References
07 Fixed in
Arch Linux
- md4c Fixed in 0.4.8-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
Debian 12
- md4c Fixed in 0.4.7-2
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- md4c Fixed in 0.4.7-2
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- md4c Fixed in 0.4.7-2
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- md4c No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.