- Exploited
- No known exploitation
- Fix
- Fixed in 0.13.6
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Uses pulldown-cmark with the ENABLE_WIKILINKS option set (including via Options::all()). Affected versions are before 0.13.6 (unaffected below 0.13.0 per the advisory metadata).
- Last modified
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 18/100
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Applications using the pulldown-cmark Markdown parser with the optional wikilink feature enabled (including via Options::all()) are affected when they parse untrusted input. Deeply nested image wikilinks cause parsing time to grow quadratically, allowing an attacker to cause excessive CPU consumption and slow down the application.
Read the original description
With Options::ENABLE_WIKILINKS, handle_wikilink builds a wikilink's target from the raw text of its body: scan_wikilink_pipe walks it looking for |, then contains('\0') and from_replace_nuls walk it again. Once a wikilink is created, disable_all_links only disables Link entries, so every enclosing ![[ stays live on the wikilink stack. On ![[![[![[…]]]]]] each of those openers then resolves in turn and rescans everything inside it, which is quadratic in the nesting depth. The event count stays tiny, because in the unpiped case each enclosing image replaces its body with a fresh text node, so all of that work is thrown away.
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 #1186 and released in 0.13.6.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach10/20Affects crates.io packages
- Severity?/10Unknown. No CVSS score or vendor rating
- No patch0/5No signal
What would change the score
- Would score about 68 if added to CISA KEV
- Would score about 63 if CISA's SSVC rates exploitation active
- Would score about 25 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Uses pulldown-cmark with the ENABLE_WIKILINKS option set (including via Options::all()). Affected versions are before 0.13.6 (unaffected below 0.13.0 per the advisory metadata).Upgrade to a fixed version: 0.13.6.
Timeline
- Advisory published5 days
- Record last updated
Affected versions
- pulldown-cmarkcrates.io
From 0.13.0 · fixed in 0.13.6
Evidence 3
- Advisory
- Repository
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about RUSTSEC-2026-0433
Is RUSTSEC-2026-0433 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
Parsing deeply nested image wikilinks takes time that grows quadratically with the nesting depth, which slows the application down. This is a denial-of-service issue caused by algorithmic complexity.Source: rustsec.org
Which versions are affected by RUSTSEC-2026-0433?
pulldown-cmark (crates.io): from 0.13.0 before 0.13.6.Source: cve.now feed data
Am I affected, and how do I check?
Versions before 0.13.6 are affected, and the advisory metadata places the start at 0.13.0. The setup involves the ENABLE_WIKILINKS option, including when it is enabled through Options::all(), in applications that parse untrusted Markdown. To check, look at the pulldown-cmark version in Cargo.lock and whether the option is set in the code.Source: rustsec.org
How do I fix RUSTSEC-2026-0433?
Upgrade pulldown-cmark to 0.13.6 or later. The advisory lists no workaround.Source: rustsec.org