How severe is GHSA-h958-fxgg-g7w3?

GHSA-h958-fxgg-g7w3 has a CVSS score of 5.9/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-h958-fxgg-g7w3?

GHSA-h958-fxgg-g7w3 affects the following packages: OPCFoundation.NetStandard.Opc.Ua.Core (NuGet). Ecosystems affected: NuGet.

How do I fix GHSA-h958-fxgg-g7w3?

Update OPCFoundation.NetStandard.Opc.Ua.Core to 1.5.374.158 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h958-fxgg-g7w3 is resolved across your whole dependency graph.

How do I detect GHSA-h958-fxgg-g7w3 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for OPCFoundation.NetStandard.Opc.Ua.Core. 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.

How do I mitigate GHSA-h958-fxgg-g7w3 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-h958-fxgg-g7w3?

O3 pinpoints whether GHSA-h958-fxgg-g7w3 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-h958-fxgg-g7w3 actively exploited in the wild?

No public exploit code has been indexed for GHSA-h958-fxgg-g7w3 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.

What is the EPSS score for GHSA-h958-fxgg-g7w3?

GHSA-h958-fxgg-g7w3 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 42th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-h958-fxgg-g7w3?

GHSA-h958-fxgg-g7w3 is classified as CWE-208 (CWE-208). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-h958-fxgg-g7w3 published, and has it been updated?

GHSA-h958-fxgg-g7w3 was published on March 3, 2025 and was last updated on May 27, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-h958-fxgg-g7w3: Security Update for the OPC UA .NET Standa…

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk42th percentile+0.51%

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.

Blast Radius

1 pkg affected

.NETOPCFoundation.NetStandard.Opc.Ua.Core

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

This security update resolves a vulnerability in the OPC UA .NET Standard Stack that allows an unauthorized attacker to bypass application authentication when the deprecated Basic128Rsa15 security policy is enabled.

Note that the Basic128Rsa15 is disabled by default so most users will not be affected. When this patch is applied the Server closes all channels using the Basic128Rsa15 if an attack is detected. This introduces a DoS before any compromise can occur which is preferable to a compromise. To prevent this failure, applications must stop using Basic128Rsa15.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`OPCFoundation.NetStandard.Opc.Ua.Core`	all versions	1.5.374.158

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for OPCFoundation.NetStandard.Opc.Ua.Core. 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 OPCFoundation.NetStandard.Opc.Ua.Core to 1.5.374.158 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h958-fxgg-g7w3 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-h958-fxgg-g7w3 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-h958-fxgg-g7w3. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

This security update resolves a vulnerability in the OPC UA .NET Standard Stack that allows an unauthorized attacker to bypass application authentication when the deprecated Basic128Rsa15 security policy is enabled. Note that the Basic128Rsa15 is disabled by default so most users will not be affected. When this patch is applied the Server closes all channels using the Basic128Rsa15 if an attack is detected. This introduces a DoS before any compromise can occur which is preferable to a compromise. To prevent this failure, applications must stop using Basic128Rsa15.

O3 Security · Impact-Aware SCA

Is GHSA-h958-fxgg-g7w3 in your dependencies?

O3 detects GHSA-h958-fxgg-g7w3 across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

GHSA-h958-fxgg-g7w3