How severe is GHSA-v5rv-hpxg-8x49?

No CVSS score has been assigned to GHSA-v5rv-hpxg-8x49 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-v5rv-hpxg-8x49?

GHSA-v5rv-hpxg-8x49 affects the following packages: ServiceStack (NuGet). Ecosystems affected: NuGet.

How do I fix GHSA-v5rv-hpxg-8x49?

Update ServiceStack to 5.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v5rv-hpxg-8x49 is resolved across your whole dependency graph.

How do I detect GHSA-v5rv-hpxg-8x49 in my NuGet dependencies?

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

How do I mitigate GHSA-v5rv-hpxg-8x49 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-v5rv-hpxg-8x49?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-v5rv-hpxg-8x49 can be triaged on real exposure rather than presence alone.

Is GHSA-v5rv-hpxg-8x49 actively exploited in the wild?

Yes. There are 3 known exploit references for GHSA-v5rv-hpxg-8x49, including 2 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for GHSA-v5rv-hpxg-8x49?

GHSA-v5rv-hpxg-8x49 has an EPSS (Exploit Prediction Scoring System) score of 2.3%, placing it in the 83th 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-v5rv-hpxg-8x49?

GHSA-v5rv-hpxg-8x49 is classified as CWE-347 (CWE-347). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-v5rv-hpxg-8x49 published, and has it been updated?

GHSA-v5rv-hpxg-8x49 was published on January 13, 2021 and was last updated on December 2, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET NuGet

Not in CISA KEV

GHSA-v5rv-hpxg-8x49 — ServiceStack

Fix: ServiceStack/ServiceStack@540d406

GHSA-v5rv-hpxg-8x49 is a CWE-347 vulnerability in ServiceStack. 3 public exploit references exist, so weaponization risk is real. A fix is available for ServiceStack — see the affected versions and patch details below.

Signature validation bypass in ServiceStack

Also known asCVE-2020-28042

Published

Jan 13, 2021

Updated

Dec 2, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

3 known

Exploitation data as of Sep 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

2.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs83th percentile — riskier than 83% of all scored CVEsHighest risk

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.

Real-World Exposure

1 pkg affected

.NETServiceStack

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

ServiceStack before 5.9.2 mishandles JWT signature verification unless an application has a custom ValidateToken function that establishes a valid minimum length for a signature.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`ServiceStack`	all versions	5.9.2`dotnet add package ServiceStack --version 5.9.2`

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

ServiceStack before 5.9.2 mishandles JWT signature verification unless a…

shielder.itNVDNov 2020

ServiceStack before 5.9.2 mishandles JWT signature verification unless a…

shielder.itNVDNov 2020

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ServiceStack, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update ServiceStack to 5.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v5rv-hpxg-8x49 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-v5rv-hpxg-8x49 can be triaged on real exposure rather than presence alone.

Tailored to GHSA-v5rv-hpxg-8x49. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

ServiceStack before 5.9.2 mishandles JWT signature verification unless an application has a custom ValidateToken function that establishes a valid minimum length for a signature.

O3 Security · Impact-Aware SCA

Is GHSA-v5rv-hpxg-8x49 in your dependencies?

O3 Security finds GHSA-v5rv-hpxg-8x49 across NuGet 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