GHSA-3pgj-pg6c-r5p7 is a medium-severity (CVSS 5.7) vulnerability in oauthlib. 3 public exploit references exist, so weaponization risk is real. A fix is available for oauthlib — see the affected versions and patch details below.
OAuthLib vulnerable to DoS when attacker provides malicious IPV6 URI
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 GHSA-3pgj-pg6c-r5p7.
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.
How urgent is this, really
GHSA-3pgj-pg6c-r5p7 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
oauthlibReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact
- Attacker providing malicious redirect uri can cause DoS to oauthlib's web application.
- Attacker can also leverage usage of
uri_validatefunctions depending where it is used.
What kind of vulnerability is it? Who is impacted?
Oauthlib applications using OAuth2.0 provider support or use directly uri_validate function.
Patches
Has the problem been patched? What versions should users upgrade to?
Issue fixed in 3.2.2 release.
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
The redirect_uri can be verified in web toolkit (i.e bottle-oauthlib, django-oauth-toolkit, ...) before oauthlib is called. A sample check if : is present to reject the request can prevent the DoS, assuming no port or IPv6 is fundamentally required.
References
Attack Vector:
- Attacker providing malicious redirect uri: https://github.com/oauthlib/oauthlib/blob/d4bafd9f1d0eba3766e933b1ac598cbbf37b8914/oauthlib/oauth2/rfc6749/grant_types/base.py#L232
- Vulnerable
uri_validatefunctions: https://github.com/oauthlib/oauthlib/blob/2b8a44855a51ad5a5b0c348a08c2564a2e197ea2/oauthlib/uri_validate.py
PoC
is_absolute_uri("http://[:::::::::::::::::::::::::::::::::::::::]/path")
Acknowledgement
Special thanks to Sebastian Chnelik - PyUp.io
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | oauthlib | ≥ 3.1.1&&< 3.2.2 | 3.2.2pip install --upgrade 'oauthlib==3.2.2' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for oauthlib, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update oauthlib to 3.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3pgj-pg6c-r5p7 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-3pgj-pg6c-r5p7 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-3pgj-pg6c-r5p7. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 9 | fence-agents-0:4.10.0-43.el9 | RHSA-2023:2161 |
Frequently Asked Questions
Is GHSA-3pgj-pg6c-r5p7 in your dependencies?
O3 Security finds GHSA-3pgj-pg6c-r5p7 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.