How severe is GHSA-jgvr-6x5w-hx5w?

No CVSS score has been assigned to GHSA-jgvr-6x5w-hx5w yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-jgvr-6x5w-hx5w?

GHSA-jgvr-6x5w-hx5w affects the following packages: kcl-lib (crates.io), zoo-kcl (PyPI). Ecosystems affected: crates.io, PyPI.

How do I fix GHSA-jgvr-6x5w-hx5w?

Update kcl-lib to 0.3.129 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jgvr-6x5w-hx5w is resolved across your whole dependency graph.

How do I detect GHSA-jgvr-6x5w-hx5w in my crates.io, PyPI dependencies?

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

How do I mitigate GHSA-jgvr-6x5w-hx5w if there is no patch (or I can't update yet)?

Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.

Is GHSA-jgvr-6x5w-hx5w actively exploited in the wild?

No public exploit code has been indexed for GHSA-jgvr-6x5w-hx5w 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.

When was GHSA-jgvr-6x5w-hx5w published, and has it been updated?

GHSA-jgvr-6x5w-hx5w was published on August 20, 2026 and was last updated on August 20, 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🐍 PyPI

Not in CISA KEV

GHSA-jgvr-6x5w-hx5w — kcl-lib

GHSA-jgvr-6x5w-hx5w is a remote code execution vulnerability in kcl-lib. A fix is available for kcl-lib — see the affected versions and patch details below.

Zoo Design Studio: Recursive KCL parsing is vulnerable to denial-of-service

Published

Aug 20, 2026

Updated

Aug 20, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Aug 20, 2026 · OSV.dev, FIRST.org (EPSS)

Real-World Exposure

2 pkgs affected

🦀kcl-lib🐍zoo-kcl

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io, PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Impact

Feeding a KCL program that wraps an expression in deep, unnecessary parentheses triggers the parser’s recursive expression -> unnecessarily_bracketed -> expression path. With enough nesting, the call stack grows until it exceeds the process stack limit, causing a stack overflow.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`kcl-lib`	all versions	0.3.129`cargo update -p kcl-lib --precise 0.3.129`
🐍PyPI	`zoo-kcl`	all versions	0.3.129`pip install --upgrade 'zoo-kcl==0.3.129'`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for kcl-lib, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update kcl-lib to 0.3.129 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jgvr-6x5w-hx5w is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.

Frequently Asked Questions

### Impact Feeding a KCL program that wraps an expression in deep, unnecessary parentheses triggers the parser’s recursive `expression` -> `unnecessarily_bracketed` -> `expression` path. With enough nesting, the call stack grows until it exceeds the process stack limit, causing a stack overflow.

O3 Security · Impact-Aware SCA

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