CVE-2025-58369
FS2 half-shutdown of socket during TLS handshake may result in spin loop on opposite side
Impact
### Impact When establishing a TLS session using `fs2-io` on the JVM using the `fs2.io.net.tls` package, 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. This CPU is consumed until the overall connection is closed. This could be used as a denial of service attack on an fs2-io powered server -- for example, by opening many connections and putting them in a half-shutdown state. Note: this issue impacts ember backed http4s servers with HTTPS as a result of ember using fs2's TLS support. ### Patches Fixed in fs2 3.12.2 and 3.13.0-M7. ### Workarounds No workarounds. ### For more information If you have any questions or comments about this advisory: [Open an issue.](https://github.com/typelevel/fs2/issues/new/choose) Contact the [Typelevel Security Team](https://github.com/typelevel/.github/blob/main/SECURITY.md).
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | co.fs2:fs2-io_2.12 | >= 3.13.0-M1, < 3.13.0-M7 | 3.13.0-M7 |
| maven | co.fs2:fs2-io_2.13 | >= 3.13.0-M1, < 3.13.0-M7 | 3.13.0-M7 |
| maven | co.fs2:fs2-io_3 | >= 3.13.0-M1, < 3.13.0-M7 | 3.13.0-M7 |
| maven | co.fs2:fs2-io_0.26 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_0.27 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_2.11 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_2.12.0-M4 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_2.12.0-RC1 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_2.12.0-M5 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_2.12.0-RC2 | < 2.5.13 | none recorded |
| maven | co.fs2:fs2-io_2.13.0-M5 | < 2.5.13 | none recorded |
Affected products
| Product | Affected versions |
|---|---|
| Fs2 Is A Compositional, Streaming I/O Library For Scala. | through 2.5.12 |
| 3.0.0-M1 | through 3.12.2 |
| And 3.13.0-M1 | through 3.13.0-M6 |
Versions were read from the advisory text. No structured product data has been published for this record yet.
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- 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/issues/3590
- 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/security/advisories/GHSA-rrw2-px9j-qffj
- https://github.com/advisories/GHSA-rrw2-px9j-qffj
- https://nvd.nist.gov/vuln/detail/CVE-2025-58369
- https://github.com/typelevel/fs2/pull/3624