How severe is GHSA-vc89-hccf-rq55?

GHSA-vc89-hccf-rq55 has a CVSS score of 5.9/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-vc89-hccf-rq55?

GHSA-vc89-hccf-rq55 affects the following packages: org.typelevel:jawn-parser_0.25 (Maven), org.typelevel:jawn-parserg (Maven), org.typelevel:jawn-parser_0.27 (Maven), org.typelevel:jawn-parser_2.10 (Maven), org.typelevel:jawn-parser_2.11 (Maven), org.typelevel:jawn-parser_2.12 (Maven), org.typelevel:jawn-parser_2.13 (Maven), org.typelevel:jawn-parser_2.13.0-M5 (Maven), and 10 more. Ecosystems affected: Maven.

How do I fix GHSA-vc89-hccf-rq55?

No patched version of org.typelevel:jawn-parser_0.25 has shipped for GHSA-vc89-hccf-rq55 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.

How do I detect GHSA-vc89-hccf-rq55 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.typelevel:jawn-parser_0.25, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-vc89-hccf-rq55 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-vc89-hccf-rq55 actively exploited in the wild?

Yes. There are 1 known exploit references for GHSA-vc89-hccf-rq55, 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-vc89-hccf-rq55?

GHSA-vc89-hccf-rq55 has an EPSS (Exploit Prediction Scoring System) score of 0.8%, placing it in the 55th 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-vc89-hccf-rq55?

GHSA-vc89-hccf-rq55 is classified as Uncontrolled Resource Consumption (CWE-400), CWE-326 (CWE-326). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-vc89-hccf-rq55 published, and has it been updated?

GHSA-vc89-hccf-rq55 was published on January 6, 2022 and was last updated on December 16, 2025. 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

MEDIUM severity

Hash collision in typelevel jawnGHSA-vc89-hccf-rq55

MEDIUMFix: typelevel/jawn#390

GHSA-vc89-hccf-rq55 is a medium-severity (CVSS 5.9) Uncontrolled Resource Consumption vulnerability in org.typelevel:jawn-parser_0.25. 1 public exploit reference exists, so weaponization risk is real. A fix is available for org.typelevel:jawn-parser_0.25 — see the affected versions and patch details below.

Also known asCVE-2022-21653

Published

Jan 6, 2022

Updated

Dec 16, 2025

Affected

18 pkgs

Patched

3 / 18

Exploits

1 known

Exploitation data as of Oct 12, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for GHSA-vc89-hccf-rq55.

EPSS Exploitation Probability

via FIRST.org ↗

0.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs55th percentile — riskier than 55% of all scored CVEsHighest risk

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

How urgent is this, really

GHSA-vc89-hccf-rq55 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

18 pkgs affected

☕org.typelevel:jawn-parser_0.25☕org.typelevel:jawn-parserg☕org.typelevel:jawn-parser_0.27☕org.typelevel:jawn-parser_2.10☕org.typelevel:jawn-parser_2.11☕org.typelevel:jawn-parser_2.12☕org.typelevel:jawn-parser_2.13☕org.typelevel:jawn-parser_2.13.0-M5+10 more

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

Impact

Extenders of the org.typelevel.jawn.SimpleFacade and org.typelevel.jawn.MutableFacade who don't override objectContext() are vulnerable to a hash collision attack. Most applications do not implement these traits directly, but inherit from a library:

Affected implementations include:

org.http4s :: http4s-play-json
org.typelevel :: jawn-ast (< 0.8.0)
org.typelevel :: jawn-play (discontinued)
org.typelevel :: jawn-rojoma (discontinued)
org.typelevel :: jawn-spray (discontinued)

Unaffected implementations include:

io.argonaut :: argonaut-jawn
io.circe :: circe-parser
org.typelevel :: jawn-ast (>= 0.8.0)
org.typelevel :: jawn-json4s (discontinued)
org.typelevel :: jawn-argonaut (discontinued)

Patches

jawn-parser-1.3.2 fixes the issue.

Workarounds

Override objectContext() to use a collision-safe collection. See the patch for an example in both SimpleFacade and MutableFacade.

References

https://github.com/typelevel/jawn/pull/390

Credits

@kag0, for the report and the patch

For more information

If you have any questions or comments about this advisory:

Open an issue in typelevel/jawn
E-mail a maintainer:
- @rossabaker

Affected Packages

18 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.typelevel:jawn-parser_0.25`	all versions	No fix
☕Maven	`org.typelevel:jawn-parserg`	all versions	No fix
☕Maven	`org.typelevel:jawn-parser_0.27`	all versions	No fix
☕Maven	`org.typelevel:jawn-parser_2.10`	all versions	No fix
☕Maven	`org.typelevel:jawn-parser_2.11`	all versions	No fix
☕Maven	`org.typelevel:jawn-parser_2.12`	all versions	1.3.2`org.typelevel:jawn-parser_2.12:1.3.2`

Affected Products

1 product · 1 configurations

Application

jawntypelevel

< 1.3.2

range

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.

Jawn is an open source JSON parser. Extenders of the `org.typelevel.jawn…

github.comNVDJan 2022

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_0.25, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
No patched version of org.typelevel:jawn-parser_0.25 has shipped for GHSA-vc89-hccf-rq55 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
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

### Impact Extenders of the `org.typelevel.jawn.SimpleFacade` and `org.typelevel.jawn.MutableFacade` who don't override `objectContext()` are vulnerable to a hash collision attack. Most applications do not implement these traits directly, but inherit from a library: Affected implementations include: * `org.http4s` :: `http4s-play-json` * `org.typelevel :: jawn-ast` (< 0.8.0) * `org.typelevel :: jawn-play` (discontinued) * `org.typelevel :: jawn-rojoma` (discontinued) * `org.typelevel :: jawn-spray` (discontinued) Unaffected implementations include: * `io.argonaut :: argonaut-jawn` * `io.ci

O3 Security · Impact-Aware SCA

Is GHSA-vc89-hccf-rq55 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

5.9/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Raw vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE Classification

CWE-400Uncontrolled Resource Consumption CWE-326CWE-326

Weaponization

No known public exploit tooling found.

Timeline

Disclosed

Jan 6, 2022

First exploit

Jan 12, 2022

6 days after disclosure — rapid exploitation

Last updated

Dec 16, 2025

Identifiers

GHSA-vc89-hccf-rq55

References

Advisorynvd.nist.gov Webgithub.com Webgithub.com Packagegithub.com

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs with CWE-400 are rated as high or higher (top: high).

CVE-2026-33625CVE-2026-81875CVE-2026-68537CVE-2026-85721CVE-2026-69147CVE-2026-86000CVE-2026-81876CVE-2026-68523Browse all CWE-400

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedDec 16, 2025