How severe is GHSA-2cpx-6pqp-wf35?

GHSA-2cpx-6pqp-wf35 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by GHSA-2cpx-6pqp-wf35?

GHSA-2cpx-6pqp-wf35 affects the following packages: co.fs2:fs2-io (Maven), co.fs2:fs2-io_2.12 (Maven), co.fs2:fs2-io_3 (Maven), co.fs2:fs2-io_2.13 (Maven), co.fs2:fs2-io_sjs1_2.13 (Maven), co.fs2:fs2-io_sjs1_3 (Maven). Ecosystems affected: Maven.

How do I fix GHSA-2cpx-6pqp-wf35?

Update co.fs2:fs2-io to 3.2.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2cpx-6pqp-wf35 is resolved across your whole dependency graph.

How do I detect GHSA-2cpx-6pqp-wf35 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for co.fs2:fs2-io, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-2cpx-6pqp-wf35 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.

Is GHSA-2cpx-6pqp-wf35 actively exploited in the wild?

Yes. There are 1 known exploit references for GHSA-2cpx-6pqp-wf35, 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-2cpx-6pqp-wf35?

GHSA-2cpx-6pqp-wf35 has an EPSS (Exploit Prediction Scoring System) score of 0.8%, placing it in the 58th 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-2cpx-6pqp-wf35?

GHSA-2cpx-6pqp-wf35 is classified as CWE-295 (CWE-295). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-2cpx-6pqp-wf35 published, and has it been updated?

GHSA-2cpx-6pqp-wf35 was published on July 29, 2022 and was last updated on September 30, 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

CRITICAL severity

fs2-io skips mTLS client verificationGHSA-2cpx-6pqp-wf35

CRITICALFix: typelevel/fs2@19ce392

GHSA-2cpx-6pqp-wf35 is a critical-severity (CVSS 9.8) CWE-295 vulnerability in co.fs2:fs2-io. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for co.fs2:fs2-io — see the affected versions and patch details below.

Also known asCVE-2022-31183

Published

Jul 29, 2022

Updated

Sep 30, 2025

Affected

6 pkgs

Patched

6 / 6

Exploits

1 known

Exploitation data as of Nov 8, 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.
CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA’s SSVC triage for GHSA-2cpx-6pqp-wf35.

EPSS Exploitation Probability

via FIRST.org ↗

0.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs58th percentile — riskier than 58% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

6 pkgs affected

☕co.fs2:fs2-io☕co.fs2:fs2-io_2.12☕co.fs2:fs2-io_3☕co.fs2:fs2-io_2.13☕co.fs2:fs2-io_sjs1_2.13☕co.fs2:fs2-io_sjs1_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

Impact

When establishing a server-mode TLSSocket using fs2-io on Node.js, the parameter requestCert = true is ignored, peer certificate verification is skipped, and the connection proceeds.

The vulnerability is limited to:

fs2-io running on Node.js. The JVM TLS implementation is completely independent.
TLSSockets in server-mode. Client-mode TLSSockets are implemented via a different API.
mTLS as enabled via requestCert = true in TLSParameters. The default setting is false for server-mode TLSSockets.

It was introduced with the initial Node.js implementation of fs2-io in v3.1.0.

Patches

A patch is released in v3.2.11. The requestCert = true parameter is respected and the peer certificate is verified. If verification fails, a SSLException is raised.

Workarounds

If using an unpatched version on Node.js, do not use a server-mode TLSSocket with requestCert = true to establish a mTLS connection.

References

For more information

If you have any questions or comments about this advisory:

Open an issue.
Contact the Typelevel Security Team.

Affected Packages

6 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`co.fs2:fs2-io`	≥ 3.1.0&&< 3.2.11	3.2.11`co.fs2:fs2-io:3.2.11`
☕Maven	`co.fs2:fs2-io_2.12`	≥ 3.1.0&&< 3.2.11	3.2.11`co.fs2:fs2-io_2.12:3.2.11`
☕Maven	`co.fs2:fs2-io_3`	≥ 3.1.0&&< 3.2.11	3.2.11`co.fs2:fs2-io_3:3.2.11`
☕Maven	`co.fs2:fs2-io_2.13`	≥ 3.1.0&&< 3.2.11	3.2.11`co.fs2:fs2-io_2.13:3.2.11`
☕Maven	`co.fs2:fs2-io_sjs1_2.13`	≥ 3.1.0&&< 3.2.11	3.2.11`co.fs2:fs2-io_sjs1_2.13:3.2.11`
☕Maven	`co.fs2:fs2-io_sjs1_3`	≥ 3.1.0&&< 3.2.11	3.2.11`co.fs2:fs2-io_sjs1_3:3.2.11`

Affected Products

1 product · 1 configurations

Application

fs2typelevel

≥ 3.1.0 && < 3.2.11

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.

fs2 is a compositional, streaming I/O library for Scala. When establishi…

github.comNVDAug 2022

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for co.fs2:fs2-io, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update co.fs2:fs2-io to 3.2.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2cpx-6pqp-wf35 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.

Frequently Asked Questions

### Impact When establishing a server-mode `TLSSocket` using `fs2-io` on Node.js, the parameter `requestCert = true` is ignored, peer certificate verification is skipped, and the connection proceeds. The vulnerability is limited to: 1. `fs2-io` running on Node.js. The JVM TLS implementation is completely independent. 2. `TLSSocket`s in server-mode. Client-mode `TLSSocket`s are implemented via a different API. 3. mTLS as enabled via `requestCert = true` in `TLSParameters`. The default setting is `false` for server-mode `TLSSocket`s. It was introduced with the initial Node.js implementation o