Vulnerability · Published Mar 19, 2021 · Assigned by mitre
CVE-2021-28834
Critical 9.8
In plain English
A critical-severity security flaw in the ruby-kramdown package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.7% (higher than 86% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)9.8Critical
Exploit odds (30 days)2.7%top 14.0% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
Kramdown before 2.3.1 does not restrict Rouge formatters to the Rouge::Formatters namespace, and thus arbitrary classes can be instantiated.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | ruby-kramdown | 2.3.0-5 | DEBIAN-CVE-2021-28834 |
| Debian:13 | ruby-kramdown | 2.3.0-5 | DEBIAN-CVE-2021-28834 |
| Debian:14 | ruby-kramdown | 2.3.0-5 | DEBIAN-CVE-2021-28834 |
| RubyGems | kramdown | 2.3.1 | GHSA-52p9-v744-mwjj |
Affected products (as reported)
References
- https://github.com/gettalong/kramdown/pull/708 x_refsource_MISC
- https://gitlab.com/gitlab-org/gitlab/-/commit/179329b5c3c118924fb242dc449d06b4ed6ccb66 x_refsource_MISC
- https://github.com/gettalong/kramdown/compare/REL_2_3_0...REL_2_3_1 x_refsource_MISC
- FEDORA-2021-139a6a2f9d vendor-advisory, x_refsource_FEDORA
- FEDORA-2021-4c57a892d1 vendor-advisory, x_refsource_FEDORA
- FEDORA-2021-edc673e864 vendor-advisory, x_refsource_FEDORA
- DSA-4890 vendor-advisory, x_refsource_DEBIAN