How severe is GHSA-w277-wpqf-rcfv?

No CVSS score has been assigned to GHSA-w277-wpqf-rcfv yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-w277-wpqf-rcfv?

GHSA-w277-wpqf-rcfv affects the following packages: svix (crates.io). Ecosystems affected: crates.io.

How do I fix GHSA-w277-wpqf-rcfv?

Update svix to 1.17.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w277-wpqf-rcfv is resolved across your whole dependency graph.

How do I detect GHSA-w277-wpqf-rcfv in my crates.io dependencies?

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

How do I mitigate GHSA-w277-wpqf-rcfv 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-w277-wpqf-rcfv?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-w277-wpqf-rcfv can be triaged on real exposure rather than presence alone.

Is GHSA-w277-wpqf-rcfv actively exploited in the wild?

No public exploit code has been indexed for GHSA-w277-wpqf-rcfv 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-w277-wpqf-rcfv?

GHSA-w277-wpqf-rcfv has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 35th 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-w277-wpqf-rcfv?

GHSA-w277-wpqf-rcfv is classified as CWE-288 (CWE-288), CWE-347 (CWE-347). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-w277-wpqf-rcfv published, and has it been updated?

GHSA-w277-wpqf-rcfv was published on February 6, 2024 and was last updated on February 3, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

Withdrawn — this advisory has been retracted

🦀 crates.io

Not in CISA KEV

GHSA-w277-wpqf-rcfv — svix

Fix: svix/svix-webhooks#1190

GHSA-w277-wpqf-rcfv is a CWE-288 vulnerability in svix. A fix is available for svix — see the affected versions and patch details below.

Duplicate Advisory: Svix vulnerable to improper comparison of different-length signatures

Also known asCVE-2024-21491 GHSA-747x-5m58-mq97RUSTSEC-2024-0010

Published

Feb 6, 2024

Updated

Feb 3, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 21, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for GHSA-w277-wpqf-rcfv.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs35th percentile — riskier than 35% 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

🦀svix

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

Versions of the package svix before 1.17.0 are vulnerable to Authentication Bypass due to an issue in the verify function where signatures of different lengths are incorrectly compared. An attacker can bypass signature verification by providing a shorter signature that matches the beginning of the actual signature.

Note:

The attacker would need to know a victim uses the Rust library for verification,no easy way to automatically check that; and uses webhooks by a service that uses Svix, and then figure out a way to craft a malicious payload that will actually include all of the correct identifiers needed to trick the receivers to cause actual issues.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`svix`	all versions	1.17.0`cargo update -p svix --precise 1.17.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for svix, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update svix to 1.17.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w277-wpqf-rcfv 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-w277-wpqf-rcfv can be triaged on real exposure rather than presence alone.

Tailored to GHSA-w277-wpqf-rcfv. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

## Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-747x-5m58-mq97. This link is maintained to preserve external references. ## Original Description The `Webhook::verify` function incorrectly compared signatures of different lengths - the two signatures would only be compared up to the length of the shorter signature. This allowed an attacker to pass in `v1,` as the signature, which would always pass verification.

O3 Security · Impact-Aware SCA

Is GHSA-w277-wpqf-rcfv in your dependencies?

O3 Security finds GHSA-w277-wpqf-rcfv 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