RUSTSEC-2026-0414
Exponential event growth with `ENABLE_WIKILINKS`
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 and released in 0.13.5.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
What each source reports
OSV Score used
Exponential event growth with `ENABLE_WIKILINKS`
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 and released in 0.13.5.
- Record
RUSTSEC-2026-0414- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pulldown-cmarkcrates.io |
0.13.0 up to 0.13.5 | 0.13.5 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
RUSTSEC-2026-0414 is a high vulnerability (CVSS 7.5) in pulldown-cmark, published October 18, 2026. No source lists public exploit code. Fixed in pulldown-cmark 0.13.5.