CVE-2026-72701 — getgrav/grav
CVE-2026-72701 is a CWE-208 vulnerability in getgrav/grav. A fix is available for getgrav/grav — see the affected versions and patch details below.
Grav CMS before 2.0.16 Timing Attack via verifyNonce
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-72701.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
getgrav/gravReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Grav CMS before 2.0.16 contains a timing vulnerability in Utils::verifyNonce() that uses non-constant-time string comparison with the === operator instead of hash_equals() for CSRF nonce validation. Attackers can measure response timing differences to recover valid nonce values byte-by-byte through multiple requests, weakening CSRF protection below its intended security margin.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getgrav/grav | all versions | 2.0.16composer require getgrav/grav:^2.0.16 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update getgrav/grav to 2.0.16 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-72701 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-72701 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-72701. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-72701 in your dependencies?
O3 Security finds CVE-2026-72701 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.