How severe is GHSA-xgp8-3hg3-c2mh?

GHSA-xgp8-3hg3-c2mh has a CVSS score of 2.2/10, rated LOW. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-xgp8-3hg3-c2mh?

GHSA-xgp8-3hg3-c2mh affects the following packages: rustls-webpki (crates.io), rustls-webpki (crates.io). Ecosystems affected: crates.io.

How do I fix GHSA-xgp8-3hg3-c2mh?

Update rustls-webpki to 0.103.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xgp8-3hg3-c2mh is resolved across your whole dependency graph.

How do I detect GHSA-xgp8-3hg3-c2mh in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rustls-webpki, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-xgp8-3hg3-c2mh if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-xgp8-3hg3-c2mh?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-xgp8-3hg3-c2mh can be triaged on real exposure rather than presence alone.

Is GHSA-xgp8-3hg3-c2mh actively exploited in the wild?

No public exploit code has been indexed for GHSA-xgp8-3hg3-c2mh yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was GHSA-xgp8-3hg3-c2mh published, and has it been updated?

GHSA-xgp8-3hg3-c2mh was published on April 16, 2026 and was last updated on September 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🦀

🦀 crates.io

Not in CISA KEV

LOW severity

GHSA-xgp8-3hg3-c2mh — rustls-webpki

LOW

GHSA-xgp8-3hg3-c2mh is a low-severity (CVSS 2.2) vulnerability in rustls-webpki. A fix is available for rustls-webpki — see the affected versions and patch details below.

webpki: Name constraints were accepted for certificates asserting a wildcard name

Also known asRUSTSEC-2026-0099

Published

Apr 16, 2026

Updated

Sep 10, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Sep 10, 2026 · OSV.dev, FIRST.org (EPSS)

Real-World Exposure

2 pkgs affected

🦀rustls-webpki🦀rustls-webpki

Real-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

Permitted subtree name constraints for DNS names were accepted for certificates asserting a wildcard name.

This was incorrect because, given a name constraint of accept.example.com, *.example.com could feasibly allow a name of reject.example.com which is outside the constraint. This is very similar to CVE-2025-61727.

Since name constraints are restrictions on otherwise properly-issued certificates, this bug is reachable only after signature verification and requires misissuance to exploit.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`rustls-webpki`	≥ 0.101.0&&< 0.103.12	0.103.12`cargo update -p rustls-webpki --precise 0.103.12`
🦀crates.io	`rustls-webpki`	≥ 0.104.0-alpha.1&&< 0.104.0-alpha.6	0.104.0-alpha.6`cargo update -p rustls-webpki --precise 0.104.0-alpha.6`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rustls-webpki, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update rustls-webpki to 0.103.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xgp8-3hg3-c2mh 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-xgp8-3hg3-c2mh can be triaged on real exposure rather than presence alone.

Tailored to GHSA-xgp8-3hg3-c2mh. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Permitted subtree name constraints for DNS names were accepted for certificates asserting a wildcard name. This was incorrect because, given a name constraint of `accept.example.com`, `*.example.com` could feasibly allow a name of `reject.example.com` which is outside the constraint. This is very similar to [CVE-2025-61727](https://go.dev/issue/76442). Since name constraints are restrictions on otherwise properly-issued certificates, this bug is reachable only after signature verification and requires misissuance to exploit.

O3 Security · Impact-Aware SCA

Is GHSA-xgp8-3hg3-c2mh in your dependencies?

O3 Security finds GHSA-xgp8-3hg3-c2mh across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works