CVE-2026-72705
Rocq Prover before 9.2.0 Guard Checker Accepts Fixpoint Passed as a Higher-Order Argument
- Published
- Updated
- Reserved
- Assigned by
- VulnCheck
Description
The guard checker in Rocq Prover does not follow recursive calls made through a fixpoint's own arguments. A fixpoint may pass itself as a higher-order argument to a second fixpoint, which then applies it to a value that is not a subterm of the structural argument. Passing the recursive function to a plain definition is rejected because the checker unfolds the definition and observes the call, but passing it to a fixpoint is accepted because higher-order recursive calls through fixpoint arguments are not tracked. This admits a type that is definitionally equal to its own negation, so self-application produces False in purely definitional code, without tactics, axioms, plugins or unsafe flags, and Print Assumptions reports the result as closed under the global context. Fixed in Rocq 9.2.0.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By VulnCheck
- 14 days later
· 14 days later
Published
- 2 months later
· 2 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulnCheckCNA (assigner) | 4.0 | Medium6.8 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| VulnCheckCNA (assigner) | 3.1 | Medium6.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N |
| NVDNVD · Deferred | 4.0 | Medium6.8 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.18% · top 93% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.8.
Weakness
Affected products
- affected < 9.2.0
References (6)
- https://github.com/rocq-prover/rocq (opens in a new tab)product
- https://github.com/rocq-prover/rocq/issues/21683 (opens in a new tab)issue-tracking
- https://github.com/rocq-prover/rocq/pull/21684 (opens in a new tab)issue-trackingpatch
- https://github.com/endrazine/rocq-cve-poc-21683 (opens in a new tab)exploit
- VulnCheck Advisory: Rocq Prover before 9.2.0 Guard Checker Accepts Fixpoint Passed as a Higher-Order Argument (opens in a new tab)third-party-advisory
- http://www.openwall.com/lists/oss-security/2026/10/26/6 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-72705)Record last updated .