GHSA-wv64-j4fq-5f9x is a medium-severity (CVSS 6.8) CWE-384 vulnerability in org.http4s:http4s-client_2.12. O3 Security confirms whether GHSA-wv64-j4fq-5f9x is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Http4s: CookieJar middleware accepts arbitrary Set-Cookie domain
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-wv64-j4fq-5f9x.
Real-World Exposure
org.http4s:http4s-client_2.12☕org.http4s:http4s-client_2.13☕org.http4s:http4s-client_2.13☕org.http4s:http4s-client_3☕org.http4s:http4s-client_3Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
When processing a Set-Cookie from a response, the CookieJar client middleware trusts the server-supplied Domain attribute verbatim, with no check that it domain-matches the host that sent the cookie (RFC6265 §5.3 step 6) and no public suffix check. A malicious or compromised server can therefore plant a cookie for any domain in the cookie jar, which is subsequently set on the client's next request to that victim domain, enabling session fixation or overwriting security-relevant cookies.
Impact
Session fixation and overwrite of security-relevant cookies for arbitrary domains contacted by the same wrapped client.
Preconditions
- Application uses the
CookieJarclient middleware. - Application contacts an attacker-controlled (or compromised) server using the same jar it uses for trusted hosts.
Workarounds
- Do not share a
CookieJaracross trusted and untrusted targets.
Note
This middleware still does not implement public suffix rejection.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.http4s:http4s-client_2.12 | all versions | 0.23.35 |
| ☕Maven | org.http4s:http4s-client_2.13 | all versions | 0.23.35 |
| ☕Maven | org.http4s:http4s-client_2.13 | ≥ 1.0.0-M1&&< 1.0.0-M47 | 1.0.0-M47 |
| ☕Maven | org.http4s:http4s-client_3 | ≥ 1.0.0-M1&&< 1.0.0-M47 | 1.0.0-M47 |
| ☕Maven | org.http4s:http4s-client_3 | all versions | 0.23.35 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.http4s:http4s-client_2.12. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.http4s:http4s-client_2.12 to 0.23.35 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wv64-j4fq-5f9x 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 pinpoints whether GHSA-wv64-j4fq-5f9x is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-wv64-j4fq-5f9x. 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-wv64-j4fq-5f9x in your dependencies?
O3 detects GHSA-wv64-j4fq-5f9x across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.