Vulnerability · Published Oct 15, 2026 · Assigned by mitre
CVE-2026-88753
High 7.5
In plain English
A high-severity uncontrolled resource consumption in the python-markdown2 package (Debian). Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.4%top 66.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
A Regular-Expression Denial of Service (ReDoS) in the Markdown2. extract_metadata() function (lib/markdown2.py) of trentm markdown2 through v2.5.5 allows attackers to cause a Denial of Service (DoS) via a crafted Markdown document.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | python-markdown2 | no fix listed | DEBIAN-CVE-2026-88753 |
| Debian:13 | python-markdown2 | no fix listed | DEBIAN-CVE-2026-88753 |
| Debian:14 | python-markdown2 | no fix listed | DEBIAN-CVE-2026-88753 |
| Ubuntu:22.04:LTS | python-markdown2 | no fix listed | UBUNTU-CVE-2026-88753 |
| Ubuntu:24.04:LTS | python-markdown2 | no fix listed | UBUNTU-CVE-2026-88753 |
| Ubuntu:26.04:LTS | python-markdown2 | no fix listed | UBUNTU-CVE-2026-88753 |
| Ubuntu:26.10 | python-markdown2 | no fix listed | UBUNTU-CVE-2026-88753 |
Affected products (as reported)
Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H