How severe is GHSA-w4cm-gvhj-cgw6?

GHSA-w4cm-gvhj-cgw6 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-w4cm-gvhj-cgw6?

GHSA-w4cm-gvhj-cgw6 affects the following packages: org.typelevel:jawn-parser_2.12 (Maven), org.typelevel:jawn-parser_2.13 (Maven), org.typelevel:jawn-parser_3 (Maven). Ecosystems affected: Maven.

How do I fix GHSA-w4cm-gvhj-cgw6?

Update org.typelevel:jawn-parser_2.12 to 1.7.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w4cm-gvhj-cgw6 is resolved across your whole dependency graph.

How do I detect GHSA-w4cm-gvhj-cgw6 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.typelevel:jawn-parser_2.12, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-w4cm-gvhj-cgw6 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is GHSA-w4cm-gvhj-cgw6 actively exploited in the wild?

No public exploit code has been indexed for GHSA-w4cm-gvhj-cgw6 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-w4cm-gvhj-cgw6?

GHSA-w4cm-gvhj-cgw6 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 46th 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-w4cm-gvhj-cgw6?

GHSA-w4cm-gvhj-cgw6 is classified as Uncontrolled Resource Consumption (CWE-400), CWE-407 (CWE-407). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-w4cm-gvhj-cgw6 published, and has it been updated?

GHSA-w4cm-gvhj-cgw6 was published on September 23, 2026 and was last updated on September 23, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

HIGH severity

Jawn: Quadratic parsing effort in AsyncParserGHSA-w4cm-gvhj-cgw6

HIGHFix: typelevel/jawn@cddcd5e

GHSA-w4cm-gvhj-cgw6 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in org.typelevel:jawn-parser_2.12. A fix is available for org.typelevel:jawn-parser_2.12 — see the affected versions and patch details below.

Also known asCVE-2026-61814

Published

Sep 23, 2026

Updated

Sep 23, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
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-w4cm-gvhj-cgw6.

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs46th percentile — riskier than 46% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

GHSA-w4cm-gvhj-cgw6 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

3 pkgs affected

☕org.typelevel:jawn-parser_2.12☕org.typelevel:jawn-parser_2.13☕org.typelevel:jawn-parser_3

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

Description

AsyncParser can be forced to perform O(n^2) work on the length of the input. When a single JSON token arrives across many small chunks, each absorb call rescans the incomplete token from the start.

Impact

Denial of service via CPU exhaustion when parsing untrusted JSON.

Preconditions:

Application uses AsyncParser
Attacker can send large tokens with control over chunk sizes.

Patches

Fixed in jawn-parser-1.7.0.

Workarounds

If you can't upgrade immediately:

Use the synchronous Parser.
Buffer incoming bytes into larger chunks before calling absorb

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.typelevel:jawn-parser_2.12`	all versions	1.7.0`org.typelevel:jawn-parser_2.12:1.7.0`
☕Maven	`org.typelevel:jawn-parser_2.13`	all versions	1.7.0`org.typelevel:jawn-parser_2.13:1.7.0`
☕Maven	`org.typelevel:jawn-parser_3`	all versions	1.7.0`org.typelevel:jawn-parser_3:1.7.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.typelevel:jawn-parser_2.12, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.typelevel:jawn-parser_2.12 to 1.7.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w4cm-gvhj-cgw6 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

`AsyncParser` can be forced to perform O(n^2) work on the length of the input. When a single JSON token arrives across many small chunks, each `absorb` call rescans the incomplete token from the start. ### Impact Denial of service via CPU exhaustion when parsing untrusted JSON. Preconditions: - Application uses `AsyncParser` - Attacker can send large tokens with control over chunk sizes. ### Patches Fixed in jawn-parser-1.7.0. ### Workarounds If you can't upgrade immediately: - Use the synchronous `Parser`. - Buffer incoming bytes into larger chunks before calling `absorb`