CVE catalog
CVE-2021-28834
ruby-kramdown: CVE-2021-28834
- Severity
- Critical · CVSS 9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 2.70% · Oct 25, 2026
Kramdown before 2.3.1 does not restrict Rouge formatters to the Rouge::Formatters namespace, and thus arbitrary classes can be instantiated.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | ruby-kramdown | sid | 2.5.2-1 | fixed |
| Debian | ruby-kramdown | forky | 2.5.2-1 | fixed |
| Debian | ruby-kramdown | trixie | 2.5.1-1 | fixed |
| Debian | ruby-kramdown | bookworm | 2.4.0-2 | fixed |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-1 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-2 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-4 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-4ubuntu0.1 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-4ubuntu0.2 | fixed |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-1 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-2 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-4 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-4ubuntu0.1 | vulnerable |
| Ubuntu | ruby-kramdown | 20.04 | 1.17.0-4ubuntu0.2 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | ruby-kramdown | source | sid | 2.3.0-5 | not yet assigned | Not reported | [985569] |
| Debian | ruby-kramdown | source | forky | 2.3.0-5 | not yet assigned | Not reported | [985569] |
| Debian | ruby-kramdown | source | trixie | 2.3.0-5 | not yet assigned | Not reported | [985569] |
| Debian | ruby-kramdown | source | bookworm | 2.3.0-5 | not yet assigned | Not reported | [985569] |
| Ubuntu | ruby-kramdown | deb | 20.04 | 1.17.0-4ubuntu0.2 | Not reported | USN-6424-1 | Not reported |
| Ubuntu | ruby-kramdown | deb | 20.04 | 1.17.0-4ubuntu0.2 | Not reported | UBUNTU-CVE-2021-28834 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [kramdown]Fixed
Source package: [ruby-kramdown]
Details (2)
2.4.0-2· all · bookwormFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · bookworm; dsa · ruby-kramdown · debian · 12
2.4.0-2· all · bookwormFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · bookworm; dsa · ruby-kramdown · debian · 12
- [ruby-kramdown]Fixed
Details (2)
2.4.0-2· all · bookwormFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · bookworm; dsa · ruby-kramdown · debian · 12
2.4.0-2· all · bookwormFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · bookworm; dsa · ruby-kramdown · debian · 12
[Debian 13 (Trixie)]
- [kramdown]Fixed
Source package: [ruby-kramdown]
Details (2)
2.5.1-1· all · trixieFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · 13
2.5.1-1· all · trixieFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · 13
- [ruby-kramdown]Fixed
Details (2)
2.5.1-1· all · trixieFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · 13
2.5.1-1· all · trixieFixed · Fixed:
2.3.0-5dsa · ruby-kramdown · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2024_11336-1.json]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2021-28834]
- [https://osv.dev/vulnerability/DSA-4890-1]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2021-28834]
- [https://osv.dev/vulnerability/USN-6424-1]
- [https://security-tracker.debian.org/tracker/CVE-2021-28834]
[Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [SUSE security advisories and VEX]