CVE-2026-72704 (GCVE-0-2026-72704)
Vulnerability from cvelistv5 – Published: 2026-08-24 20:08 – Updated: 2026-08-24 20:08
VLAI
EPSS
VEX
Title
Rocq Prover through 9.2.0 Guard Checker Trusts Corrupted Recursive Tree After Transport
Summary
The guard checker in Rocq Prover does not recheck the recursive tree representation of an inductive type parameter after that parameter has been changed by transport. A fixpoint may apply a rewrite along an equality between types to its recursive argument, which the guard checker accepts because the inductive type is preserved, while the recursive tree recorded for the parameter is altered. A second fixpoint that calls the first inherits the altered recursive tree without verification, so a call that is not structurally decreasing is accepted as terminating. The resulting non-terminating definition proves that a natural number equals its own successor and therefore False, from which any proposition follows. The demonstration uses two axioms that follow from univalence and are consistent with the calculus of inductive constructions, so the contradiction comes from the guard check rather than from the assumptions. A fix is proposed but not merged.
Severity
6.3 (Medium)
CWE
- CWE-670 - Always-Incorrect Control Flow Implementation
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/rocq-prover/rocq | product |
| https://github.com/rocq-prover/rocq/issues/22024 | issue-tracking |
| https://github.com/rocq-prover/rocq/pull/22027 | issue-tracking |
| https://github.com/endrazine/rocq-cve-poc-22024 | exploit |
| https://www.vulncheck.com/advisories/rocq-prover-… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| rocq-prover | rocq |
Affected:
0 , ≤ 9.2.0
(custom)
|
guessed |
Date Public
2026-05-13 00:00
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}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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