CVE-2026-72705 (GCVE-0-2026-72705)
Vulnerability from cvelistv5 – Published: 2026-08-24 20:08 – Updated: 2026-08-24 20:08
VLAI
EPSS
VEX
Title
Rocq Prover before 9.2.0 Guard Checker Accepts Fixpoint Passed as a Higher-Order Argument
Summary
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.
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/21683 | issue-tracking |
| https://github.com/rocq-prover/rocq/pull/21684 | issue-tracking |
| https://github.com/endrazine/rocq-cve-poc-21683 | 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
2026-02-28 00:00
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"url": "https://github.com/rocq-prover/rocq/pull/21684"
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"url": "https://github.com/endrazine/rocq-cve-poc-21683"
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"title": "Rocq Prover before 9.2.0 Guard Checker Accepts Fixpoint Passed as a Higher-Order Argument",
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"datePublished": "2026-08-24T20:08:32.535Z",
"dateReserved": "2026-08-10T13:02:52.001Z",
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"date": "2026-08-25",
"epss": "0.0012",
"percentile": "0.02035"
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"redhat_vex": {
"current_release_date": "2026-08-24T21:18:53+00:00",
"cve": "CVE-2026-72705",
"id": "CVE-2026-72705",
"initial_release_date": "2026-08-24T20:08:32.535000+00:00",
"product_status:known_not_affected": "1",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "rocq: Rocq Prover: Logical inconsistency via untracked higher-order fixpoint arguments",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-72705.json",
"version": "3"
}
}
}
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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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