Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The pulldown-cmark crate, versions 0.13.0 up to but not including 0.13.5, is vulnerable when the ENABLE_WIKILINKS option is on, including when all options are enabled. A wikilink with a pipe and empty display text, such as [[a|]], makes the number of parser events roughly double for the rest of the document, so a few kilobytes of untrusted Markdown can exhaust memory in an application that collects or renders the events. Upgrade to pulldown-cmark 0.13.5 or later. Turning off ENABLE_WIKILINKS, which is off by default, also avoids the problem.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 7.5 | High | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | OSV |
- CISA KEV Not listed.
- EPSS No score.
Timeline
- 31 Oct 2026, 14:24 UTC First seen by agentprime
- 31 Oct 2026, 14:24 UTC Confirmed by OSV