CVE-2025-39686
comedi: Make insn_rw_emulate_bits() do insn->n samples
At a glance
- Source
- NVD
- EPSS
- EPSS 0.19 % · percentile 9 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: comedi: Make insn_rw_emulate_bits() do insn->n samples The `insn_rw_emulate_bits()` function is used as a default handler for `INSN_READ` instructions for subdevices that have a handler for `INSN_BITS` but not for `INSN_READ`. Similarly, it is used as a default handler for `INSN_WRITE` instructions for subdevices that have a handler for `INSN_BITS` but not for `INSN_WRITE`. It works by emulating the `INSN_READ` or `INSN_WRITE` instruction handling with a constructed `INSN_BITS` instruction. However, `INSN_READ` and `INSN_WRITE` instructions are supposed to be able read or write multiple samples, indicated by the `insn->n` value, but `insn_rw_emulate_bits()` currently only handles a single sample. For `INSN_READ`, the comedi core will copy `insn->n` samples back to user-space. (That triggered KASAN kernel-infoleak errors when `insn->n` was greater than 1, but that is being fixed more generally elsewhere in the comedi core.) Make `insn_rw_emulate_bits()` either handle `insn->n` samples, or return an error, to conform to the general expectation for `INSN_READ` and `INSN_WRITE` handlers.
References
- https://git.kernel.org/stable/c/ab77e85bd3bc006ef40738f26f446a660813da44
- https://git.kernel.org/stable/c/ae8bc1f07bcb31b8636420e03d1f9c3df6219a2b
- https://git.kernel.org/stable/c/842f307a1d115b24f2bcb2415c4e344f11f55930
- https://git.kernel.org/stable/c/92352ed2f9ac422181e381c2430c2d0dfb46faa0
- https://git.kernel.org/stable/c/dc0a2f142d655700db43de90cb6abf141b73d908
- https://git.kernel.org/stable/c/7afba9221f70d4cbce0f417c558879cba0eb5e66
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2025-31538
- GCVE · GCVE-0-2025-39686
CERT-FR advisories
- CERTFR-2026-AVI-0565 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0246 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0227 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0218 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0194 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0169 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1135 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1075 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1073 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1032 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1009 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0921 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0895 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0894 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0825 — Multiples vulnérabilités dans le noyau Linux de Debian · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 2.6.29 < 5.15.190cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.16 < 6.1.149cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.103cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.44cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.16.4cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected ed9eccbe8970f6eedc1b978c157caf1251a896d4 < ab77e85bd3bc006ef40738f26f446a660813da44 ; affected ed9eccbe8970f6eedc1b978c157caf1251a896d4 < ae8bc1f07bcb31b8636420e03d1f9c3df6219a2b ; affected ed9eccbe8970f6eedc1b978c157caf1251a896d4 < 842f307a1d115b24f2bcb2415c4e344f11f55930 ; affected ed9eccbe8970f6eedc1b978c157caf1251a896d4 < 92352ed2f9ac422181e381c2430c2d0dfb46faa0 ; affected ed9eccbe8970f6eedc1b978c157caf1251a896d4 < dc0a2f142d655700db43de90cb6abf141b73d908 ; affected ed9eccbe8970f6eedc1b978c157caf1251a896d4 < 7afba9221f70d4cbce0f417c558879cba0eb5e66 |
| Linux · Linux | affected 2.6.29 ; unaffected 0 < 2.6.29 ; unaffected 5.15.190 ≤ 5.15.* ; unaffected 6.1.149 ≤ 6.1.* ; unaffected 6.6.103 ≤ 6.6.* ; unaffected 6.12.44 ≤ 6.12.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |