How severe is GHSA-4w2j-m93h-cj5j?

GHSA-4w2j-m93h-cj5j has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-4w2j-m93h-cj5j?

GHSA-4w2j-m93h-cj5j affects the following packages: quinn-proto (crates.io). Ecosystems affected: crates.io.

How do I fix GHSA-4w2j-m93h-cj5j?

Update quinn-proto to 0.11.15 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4w2j-m93h-cj5j is resolved across your whole dependency graph.

How do I detect GHSA-4w2j-m93h-cj5j in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for quinn-proto. 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-4w2j-m93h-cj5j 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-4w2j-m93h-cj5j?

O3 pinpoints whether GHSA-4w2j-m93h-cj5j 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-4w2j-m93h-cj5j actively exploited in the wild?

No public exploit code has been indexed for GHSA-4w2j-m93h-cj5j 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-4w2j-m93h-cj5j?

GHSA-4w2j-m93h-cj5j has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 26th 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-4w2j-m93h-cj5j?

GHSA-4w2j-m93h-cj5j is classified as CWE-770 (CWE-770). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-4w2j-m93h-cj5j published, and has it been updated?

GHSA-4w2j-m93h-cj5j was published on July 24, 2026 and was last updated on July 25, 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

GHSA-4w2j-m93h-cj5j

HIGH

Quinn: Remote memory exhaustion in quinn-proto from unbounded out-of-order stream reassembly

Also known asCVE-2026-25800RUSTSEC-2026-0185

Published

Jul 24, 2026

Updated

Jul 25, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk26th percentile0.00%

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

🦀quinn-proto

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

Summary

The Assembler component that assembles unordered stream fragments into consecutive chunks of the stream incurs some overhead for non-contiguous fragments. Readers that read from a RecvStream in order (through an AsyncRead impl for example) will be sensitive to peers that send fragments while leaving out early parts of the stream, and in particular, fragments with many gaps (because these cannot be defragmented). In such a scenario, the receiving connection suffers from high buffer overhead, enabling memory exhaustion.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`quinn-proto`	≥ 0.1.0&&< 0.11.15	0.11.15

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for quinn-proto. 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 quinn-proto to 0.11.15 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4w2j-m93h-cj5j 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-4w2j-m93h-cj5j 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-4w2j-m93h-cj5j. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

## Summary The `Assembler` component that assembles unordered stream fragments into consecutive chunks of the stream incurs some overhead for non-contiguous fragments. Readers that read from a `RecvStream` in order (through an `AsyncRead` impl for example) will be sensitive to peers that send fragments while leaving out early parts of the stream, and in particular, fragments with many gaps (because these cannot be defragmented). In such a scenario, the receiving connection suffers from high buffer overhead, enabling memory exhaustion.

O3 Security · Impact-Aware SCA

Is GHSA-4w2j-m93h-cj5j in your dependencies?

O3 detects GHSA-4w2j-m93h-cj5j 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.

Scan my dependencies How O3 SCA works