Vulnerability · Published Feb 17, 2023 · Assigned by mitre
CVE-2021-33391
Critical 9.8
In plain English
A critical-severity use-after-free in the tidy-html5 package (Debian). Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 67% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)1.1%top 33.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
An issue in HTACG HTML Tidy v5.7.28 allows attacker to execute arbitrary code via the -g option of the CleanNode() function in gdoc.c.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | tidy-html5 | no fix listed | DEBIAN-CVE-2021-33391 |
| Debian:13 | tidy-html5 | 2:5.8.0-2 | DEBIAN-CVE-2021-33391 |
| Debian:14 | tidy-html5 | 2:5.8.0-2 | DEBIAN-CVE-2021-33391 |
| Ubuntu:22.04:LTS | tidy-html5 | 2:5.6.0-11ubuntu0.22.04.1 | USN-6483-1 |
| Ubuntu:22.04:LTS | tidy-html5 | 2:5.6.0-11ubuntu0.22.04.1 | UBUNTU-CVE-2021-33391 |
| Ubuntu:24.04:LTS | tidy-html5 | 2:5.6.0-11ubuntu1 | UBUNTU-CVE-2021-33391 |
Affected products (as reported)
Weakness: CWE-416 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H