fbdev: fbcon: fix out-of-bounds read in err_out of fbcon_do_set_font() (Linux Linux)
En bref
- Source
- NVD
- EPSS
- EPSS 0.17 % · centile 7 ()
- État
- PUBLISHED
- Publiée
- Mise à jour
- Attribuée par
- Linux
- Statut NVD
- Modified
Rechercher sur…
Description
In the Linux kernel, the following vulnerability has been resolved: fbdev: fbcon: fix out-of-bounds read in err_out of fbcon_do_set_font() When fbcon_do_set_font() fails (e.g., due to a memory allocation failure inside vc_resize() under heavy memory pressure), it jumps to the `err_out` label to roll back the console state. However, the current rollback logic forgets to restore the `hi_font` state, leading to a severe state machine corruption. Earlier in the function, `set_vc_hi_font()` might be called to change `vc->vc_hi_font_mask` and mutate the screen buffer. If `vc_resize()` subsequently fails, the `err_out` path restores `vc_font.charcount` but entirely skips rolling back the `vc_hi_font_mask` and the screen buffer. This mismatch leaves the terminal in a desynchronized state. Because `vc_hi_font_mask` remains set, the VT subsystem will still accept character indices greater than 255 from userspace and write them to the screen buffer. Subsequent rendering calls (e.g., `fbcon_putcs()`) will then use these inflated indices to access the reverted, 256-character font array, leading to a deterministic out-of-bounds read and potential kernel memory disclosure. Fix this by adding the missing rollback logic for the `hi_font` mask and screen buffer in the error path.
Faiblesses (CWE)
- CWE-125 — Lecture hors limites
Références
- https://git.kernel.org/stable/c/cb016bcb40c81e7b19c4ae6143babb366dae8e20
- https://git.kernel.org/stable/c/ac562193c36696513ae196171892e9338475c4bc
- https://git.kernel.org/stable/c/3618a4c5b2591cfa83efe74f5b18c2d02b35c3f5
- https://git.kernel.org/stable/c/a7a526fbc847f07ad3a503c7382189be5ab68574
- https://git.kernel.org/stable/c/b5bb2c696e140c399cb874def2feedf61dee27d6
- https://git.kernel.org/stable/c/076b1aa65f77a49bce5a48a4a55a397cfcafa2b8
- https://git.kernel.org/stable/c/39815715cbcfabb16fc8c5f4a23deeda20f5df62
- https://git.kernel.org/stable/c/8fdc8c2057eea08d40ce2c8eed41ff9e451c65c2
Scores
| Version | Score | Vecteur | Évalué par |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H | Linux |
| CVSS 3.1 | HIGH 7.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
Références européennes
- ENISA EUVD · EUVD-2026-45457
- GCVE · GCVE-0-2026-53402
Avis du CERT-FR
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1333 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1286 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1252 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1229 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1203 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1162 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1091 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1064 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1031 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1029 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0982 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0930 — Multiples vulnérabilités dans le noyau Linux de Debian · cert.ssi.gouv.fr
Configurations affectées (CPE NVD)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.10.249 < 5.10.261cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.15.64 < 5.15.212cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.19.6 < 6.0cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.0.1 < 6.1.178cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.145cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.96cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.39cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 7.1.3cpe:2.3:o:linux:linux_kernel:6.0:-:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.0:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.0:rc5:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.0:rc6:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:6.0:rc7:*:*:*:*:*:*
Produits affectés
| Produit | Versions |
|---|---|
| Linux · Linux | affected 868749a7456dc48e93887a8474194e2ee6d6c21f < cb016bcb40c81e7b19c4ae6143babb366dae8e20 ; affected ebd6f886aa2447fcfcdce5450c9e1028e1d681bb < ac562193c36696513ae196171892e9338475c4bc ; affected a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 < 3618a4c5b2591cfa83efe74f5b18c2d02b35c3f5 ; affected a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 < a7a526fbc847f07ad3a503c7382189be5ab68574 ; affected a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 < b5bb2c696e140c399cb874def2feedf61dee27d6 ; affected a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 < 076b1aa65f77a49bce5a48a4a55a397cfcafa2b8 |
| Linux · Linux | affected 6.0 ; unaffected 0 < 6.0 ; unaffected 5.10.261 ≤ 5.10.* ; unaffected 5.15.212 ≤ 5.15.* ; unaffected 6.1.178 ≤ 6.1.* ; unaffected 6.6.145 ≤ 6.6.* |
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 |