fs2: Half-shutdown of socket during TLS handshake may result in spin loop on opposite side
Priority LOW 24CWE-400Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-400.
Summary
fs2 is a compositional, streaming I/O library for Scala. Versions up to and including 2.5.12, 3.0.0-M1 through 3.12.2, and 3.13.0-M1 through 3.13.0-M6 are vulnerable to denial of service attacks though TLS sessions using fs2-io on the JVM using the fs2.io.net.tls package. When establishing a TLS session, if one side of the connection shuts down `write` while the peer side is awaiting more data to progress the TLS handshake, the peer side will spin loop on the socket read, fully utilizing a CPU. The CPU is consumed until the overall connection is closed, potentially shutting down a fs2-io powered server. This issue is fixed in versions 2.5.13, 3.12.1, and 3.13.0-M7.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00466 40th percentileScored 2026-11-07
Fix Fixed fs2 (typelevel): 3.12.2, 3.13.0-M7, 2.5.13co.fs2:fs2-io_2.12 (Maven): 3.12.2, 3.13.0-M7, 2.5.13+2 more products
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| http4s | fs2 | 3.0.0-M1 to before 3.12.2; 3.13.0-M1 to before 3.13.0-M7; before 2.5.13 | 3.12.2, 3.13.0-M7, 2.5.13 | Patch available | CNA |
| — | co.fs2:fs2-io_2.12 (Maven) | 3.0.0-M1 to before 3.12.2 | 3.12.2 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.12 (Maven) | 3.13.0-M1 to before 3.13.0-M7 | 3.13.0-M7 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.13 (Maven) | 3.0.0-M1 to before 3.12.2 | 3.12.2 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.13 (Maven) | 3.13.0-M1 to before 3.13.0-M7 | 3.13.0-M7 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_3 (Maven) | 3.0.0-M1 to before 3.12.2 | 3.12.2 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_3 (Maven) | 3.13.0-M1 to before 3.13.0-M7 | 3.13.0-M7 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_0.26 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_0.27 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.11 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.12.0-M4 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.12.0-RC1 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.12.0-M5 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.12.0-RC2 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.13.0-M5 (Maven) | all versions | — | No fix listed | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.12 (Maven) | before 2.5.13 | 2.5.13 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_2.13 (Maven) | before 2.5.13 | 2.5.13 | Patch available | GHSA-rrw2-px9j-qffj |
| — | co.fs2:fs2-io_3 (Maven) | before 2.5.13 | 2.5.13 | Patch available | GHSA-rrw2-px9j-qffj |
- fs2 Vendorhttp4s Affected 3.0.0-M1 to before 3.12.2; 3.13.0-M1 to before 3.13.0-M7; before 2.5.13 Fixed in 3.12.2, 3.13.0-M7, 2.5.13 Patch available CNA
- co.fs2:fs2-io_2.12 (Maven) Vendor— Affected 3.0.0-M1 to before 3.12.2 Fixed in 3.12.2 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.12 (Maven) Vendor— Affected 3.13.0-M1 to before 3.13.0-M7 Fixed in 3.13.0-M7 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.13 (Maven) Vendor— Affected 3.0.0-M1 to before 3.12.2 Fixed in 3.12.2 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.13 (Maven) Vendor— Affected 3.13.0-M1 to before 3.13.0-M7 Fixed in 3.13.0-M7 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_3 (Maven) Vendor— Affected 3.0.0-M1 to before 3.12.2 Fixed in 3.12.2 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_3 (Maven) Vendor— Affected 3.13.0-M1 to before 3.13.0-M7 Fixed in 3.13.0-M7 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_0.26 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_0.27 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.11 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.12.0-M4 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.12.0-RC1 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.12.0-M5 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.12.0-RC2 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.13.0-M5 (Maven) Vendor— Affected all versions Fixed in — No fix listed GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.12 (Maven) Vendor— Affected before 2.5.13 Fixed in 2.5.13 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_2.13 (Maven) Vendor— Affected before 2.5.13 Fixed in 2.5.13 Patch available GHSA-rrw2-px9j-qffj
- co.fs2:fs2-io_3 (Maven) Vendor— Affected before 2.5.13 Fixed in 2.5.13 Patch available GHSA-rrw2-px9j-qffj
Remediation
- Fix · CNA fs2 (typelevel) Fixed in 3.12.2, 3.13.0-M7, 2.5.13
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_2.12 (Maven) Fixed in 3.12.2 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_2.12 (Maven) Fixed in 3.13.0-M7 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_2.13 (Maven) Fixed in 3.12.2 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_2.13 (Maven) Fixed in 3.13.0-M7 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_3 (Maven) Fixed in 3.12.2 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_3 (Maven) Fixed in 3.13.0-M7 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_2.12 (Maven) Fixed in 2.5.13 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_2.13 (Maven) Fixed in 2.5.13 Advisory →
- Fix · GHSA-rrw2-px9j-qffj co.fs2:fs2-io_3 (Maven) Fixed in 2.5.13 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-58369
- 2026-10-03 Alias added: GHSA-rrw2-px9j-qffj
References
Other 9
- https://github.com/typelevel/fs2/security/advisories/GHSA-rrw2-px9j-qffj
- https://github.com/typelevel/fs2/issues/3590
- https://github.com/typelevel/fs2/commit/46e2dc3abf994dcf3d0b804b2ddb3c10c04d4976
- https://github.com/typelevel/fs2/commit/5c6c4c6c1ef330f7e6b53661ecc63d5f5ba8885c
- https://github.com/typelevel/fs2/commit/edf0c4f2e660360d1c1a8c5377ce32294de89238
- https://github.com/typelevel/fs2/releases/tag/v3.12.2
- https://github.com/typelevel/fs2/releases/tag/v3.13.0-M7
- https://github.com/typelevel/fs2/pull/3624
- https://github.com/typelevel/fs2
More http4s vulnerabilities
- TI-2022-13223 mTLS client verification is skipped in fs2 on Node.js CVSS 3.1CRITICAL 9.8
- TI-2023-08714 Http4s has fatal error parsing User-Agent and Server headers CVSS 3.1HIGH 7.5
- TI-2022-06031 Hash collision in typelevel jawn CVSS 3.1HIGH 7.5
- TI-2025-37261 Http4s vulnerable to HTTP Request Smuggling due to improper handling of HTTP trailer section CVSS 4.0MEDIUM 6.3
- TI-2026-44185 http4s-scala-xml has an XML External Entity (XXE) processing issue CVSS 3.1CRITICAL 9.3
- TI-2020-04336 Local file inclusion vulnerability in http4s CVSS 3.1HIGH 7.6
Sources
- CVE-2025-58369 · CVE Program
- CVE-2025-58369 · NVD
- FIRST EPSS
- GHSA-rrw2-px9j-qffj · GitHub Advisory Database · CC BY 4.0
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