How severe is GHSA-f8vr-r385-rh5r?

No CVSS score has been assigned to GHSA-f8vr-r385-rh5r yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-f8vr-r385-rh5r?

GHSA-f8vr-r385-rh5r affects the following packages: h2 (crates.io). Ecosystems affected: crates.io.

How do I fix GHSA-f8vr-r385-rh5r?

Update h2 to 0.3.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f8vr-r385-rh5r is resolved across your whole dependency graph.

How do I detect GHSA-f8vr-r385-rh5r in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for h2. 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-f8vr-r385-rh5r 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-f8vr-r385-rh5r?

O3 pinpoints whether GHSA-f8vr-r385-rh5r 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-f8vr-r385-rh5r actively exploited in the wild?

Yes. There are 1 known exploit references for GHSA-f8vr-r385-rh5r, including 1 in-the-wild exploitation 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-f8vr-r385-rh5r?

GHSA-f8vr-r385-rh5r has an EPSS (Exploit Prediction Scoring System) score of 1.1%, placing it in the 62th 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-f8vr-r385-rh5r?

GHSA-f8vr-r385-rh5r 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-f8vr-r385-rh5r published, and has it been updated?

GHSA-f8vr-r385-rh5r was published on April 11, 2023 and was last updated on November 8, 2023. 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-f8vr-r385-rh5r

h2 vulnerable to denial of service

Also known asCVE-2023-26964RUSTSEC-2023-0034

Published

Apr 11, 2023

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

1.1%probability of exploitation in next 30 days

Lower Risk62th percentile+0.79%

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

🦀h2

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

Hyper is an HTTP library for Rust and h2 is an HTTP 2.0 client & server implementation for Rust. An issue was discovered in h2 v0.2.4 when processing header frames. It incorrectly processes the HTTP2 RST_STREAM frames by not always releasing the memory immediately upon receiving the reset frame, leading to stream stacking. As a result, the memory and CPU usage are high which can lead to a Denial of Service (DoS).

This issue affects users only when dealing with http2 connections.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`h2`	all versions	0.3.17

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.

An issue was discovered in hyper v0.13.7. h2-0.2.4 Stream stacking occur…

github.comNVDApr 2023

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for h2. 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 h2 to 0.3.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f8vr-r385-rh5r 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-f8vr-r385-rh5r 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-f8vr-r385-rh5r. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Hyper is an HTTP library for Rust and h2 is an HTTP 2.0 client & server implementation for Rust. An issue was discovered in h2 v0.2.4 when processing header frames. It incorrectly processes the HTTP2 `RST_STREAM` frames by not always releasing the memory immediately upon receiving the reset frame, leading to stream stacking. As a result, the memory and CPU usage are high which can lead to a Denial of Service (DoS). This issue affects users only when dealing with http2 connections.

O3 Security · Impact-Aware SCA

Is GHSA-f8vr-r385-rh5r in your dependencies?

O3 detects GHSA-f8vr-r385-rh5r 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