GHSA-c25x-cm9x-qqgx is a critical-severity (CVSS 9.9) Out-of-bounds Read vulnerability in Deno. 1 public exploit reference exists, so weaponization risk is real. A fix is available for Deno — see the affected versions and patch details below.
Deno improperly handles resizable ArrayBuffer
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-c25x-cm9x-qqgx.
EPSS Exploitation Probability
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.
How urgent is this, really
GHSA-c25x-cm9x-qqgx plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
Deno🦀serde_v8🦀deno_runtimeReal-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
Impact
Resizable ArrayBuffers passed to asynchronous native functions that are shrunk during the asynchronous operation could result in an out-of-bound read/write.
It is unlikely that this has been exploited in the wild, as the only version affected is Deno 1.32.0.
Deno Deploy users are not affected.
Patches
The problem has been resolved by disabling resizable ArrayBuffers temporarily in Deno 1.32.1. A future version of Deno will re-enable resizable ArrayBuffers with a proper fix.
Workarounds
Upgrade to Deno 1.32.1, or run with --v8-flags=--no-harmony-rab-gsab to disable resizable ArrayBuffers.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | Deno | ≥ 1.32.0&&< 1.32.1 | 1.32.1cargo update -p Deno --precise 1.32.1 |
| 🦀crates.io | serde_v8 | ≥ 0.87.0&&< 0.88.0 | 0.88.0cargo update -p serde_v8 --precise 0.88.0 |
| 🦀crates.io | deno_runtime | ≥ 0.102.0&&< 0.103.0 | 0.103.0cargo update -p deno_runtime --precise 0.103.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Deno, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Deno to 1.32.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c25x-cm9x-qqgx 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-c25x-cm9x-qqgx can be triaged on real exposure rather than presence alone.
Tailored to GHSA-c25x-cm9x-qqgx. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-c25x-cm9x-qqgx in your dependencies?
O3 Security finds GHSA-c25x-cm9x-qqgx across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.