GHSA-237r-r8m4-4q88 — guzzlehttp/oauth-subscrib…
Fix: guzzle/oauth-subscriber@92b619bGHSA-237r-r8m4-4q88 is a CWE-338 vulnerability in guzzlehttp/oauth-subscriber. A fix is available for guzzlehttp/oauth-subscriber — see the affected versions and patch details below.
Guzzle OAuth Subscriber has insufficient nonce entropy
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-237r-r8m4-4q88.
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
guzzlehttp/oauth-subscriberReal-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
Impact
Nonce generation does not use sufficient entropy nor a cryptographically secure pseudorandom source (https://github.com/guzzle/oauth-subscriber/blob/0.8.0/src/Oauth1.php#L192). This can leave servers vulnerable to replay attacks when TLS is not used.
Patches
Upgrade to version 0.8.1 or higher.
Workarounds
No.
References
Issue is similar to https://nvd.nist.gov/vuln/detail/CVE-2025-22376.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | guzzlehttp/oauth-subscriber | all versions | 0.8.1composer require guzzlehttp/oauth-subscriber:^0.8.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for guzzlehttp/oauth-subscriber, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update guzzlehttp/oauth-subscriber to 0.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-237r-r8m4-4q88 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 GHSA-237r-r8m4-4q88 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-237r-r8m4-4q88. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-237r-r8m4-4q88 in your dependencies?
O3 Security finds GHSA-237r-r8m4-4q88 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.