RUSTSEC-2026-0414 json
Exponential event growth with `ENABLE_WIKILINKS`
published 24d ago modified 15d ago
- cvss
- 7.5
- version 3.1, OSV
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- —
- no score, EPSS covers CVEs only
- public exploits
- 0
- none known
Summary
When `Options::ENABLE_WIKILINKS` is enabled, a wikilink with a pipe separator and empty display text, such as `[[a|]]`, leaks its child node's sibling chain into the content that follows it. Each such link roughly doubles the number of events the parser yields for the rest of the document, so output grows exponentially with input size: 16 repetitions of `[[a|]] ` (112 bytes) yield 327,676 events, where the fixed parser yields 65. A document of a few kilobytes is enough to exhaust memory in a process that collects the events or renders them to HTML.
Applications that parse untrusted Markdown with `ENABLE_WIKILINKS` set, including through `Options::all()`, are affected. The option is off by default. Parsing without it is not affected.
The flaw was fixed in [#1102](https://github.com/pulldown-cmark/pulldown-cmark/pull/1102) and released in 0.13.5.
Patch / fix
Is RUSTSEC-2026-0414 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| OSV | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | pulldown-cmark | >=0.13.0, <0.13.5 |
0.13.5 |
References
Sources
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.