GHSA-h8jm-2x53-xhp5
HIGHGHSA-h8jm-2x53-xhp5 is a high-severity (CVSS 7.5) CWE-120 vulnerability in openssl-src. 2 public exploit references exist, so weaponization risk is real. O3 Security confirms whether GHSA-h8jm-2x53-xhp5 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
X.509 Email Address Variable Length Buffer Overflow
Blast Radius
openssl-srcReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
A buffer overrun can be triggered in X.509 certificate verification,
specifically in name constraint checking. Note that this occurs after
certificate chain signature verification and requires either a CA to
have signed a malicious certificate or for an application to continue
certificate verification despite failure to construct a path to a trusted
issuer. An attacker can craft a malicious email address in a certificate
to overflow an arbitrary number of bytes containing the . character
(decimal 46) on the stack. This buffer overflow could result in a crash
(causing a denial of service).
In a TLS client, this can be triggered by connecting to a malicious server. In a TLS server, this can be triggered if the server requests client authentication and a malicious client connects.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | openssl-src | ≥ 300.0.0&&< 300.0.11 | 300.0.11 |
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 openssl-src. 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 openssl-src to 300.0.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h8jm-2x53-xhp5 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-h8jm-2x53-xhp5 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-h8jm-2x53-xhp5. 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-h8jm-2x53-xhp5 in your dependencies?
O3 detects GHSA-h8jm-2x53-xhp5 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.