- 7.8HighCVSS base score
- 0.15%Exploitation in 30 daysEPSS · top 96% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: fbcon: Set fb_display[i]->mode to NULL when the mode is released Recently, we discovered the following issue through syzkaller: BUG: KASAN: slab-use-after-free in fb_mode_is_equal+0x285/0x2f0 Read of size 4 at addr ff11000001b3c69c by task syz.xxx ... Call Trace: <TASK> dump_stack_lvl+0xab/0xe0 print_address_description.constprop.0+0x2c/0x390 print_report+0xb9/0x280 kasan_report+0xb8/0xf0 fb_mode_is_equal+0x285/0x2f0 fbcon_mode_deleted+0x129/0x180 fb_set_var+0xe7f/0x11d0 do_fb_ioctl+0x6a0/0x750 fb_ioctl+0xe0/0x140 __x64_sys_ioctl+0x193/0x210 do_syscall_64+0x5f/0x9c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Based on experimentation and analysis, during framebuffer unregistration, only the memory of fb_info->modelist is freed, without setting the corresponding fb_display[i]->mode to NULL for the freed modes. This leads to UAF issues during subsequent accesses. Here's an example of reproduction steps: 1. With /dev/fb0 already registered in the system, load a kernel module to register a new device /dev/fb1; 2. Set fb1's mode to the global fb_display[] array (via FBIOPUT_CON2FBMAP); 3. Switch console from fb to VGA (to allow normal rmmod of the ko); 4. Unload the kernel module, at this point fb1's modelist is freed, leaving a wild pointer in fb_display[]; 5. Trigger the bug via system calls through fb0 attempting to delete a mode from fb0. Add a check in do_unregister_framebuffer(): if the mode to be freed exists in fb_display[], set the corresponding mode pointer to NULL.
Timeline
ID reserved
By Linux
- 8 months later
· 8 months later
Published
- 10 months later
· 10 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Deferred | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.15% · top 96% of all CVEs (10 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 39c2c1a2773aaf73e56906e5ef670114eb2d354f
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 4ac18f0e6a6d599ca751c4cd98e522afc8e3d4eb
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < 468f78276a37f4c6499385a4ce28f4f57be6655d
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < c079d42f70109512eee49123a843be91d8fa133f
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < de89d19f4f30d9a8de87b9d08c1bd35cb70576d8
- affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 – < a1f3058930745d2b938b6b4f5bd9630dc74b26b7
- affected 2.6.12
- unaffected < 2.6.12
- unaffected 5.15.203 – ≤ 5.15.*
- unaffected 6.1.159 – ≤ 6.1.*
- unaffected 6.6.117 – ≤ 6.6.*
- unaffected 6.12.58 – ≤ 6.12.*
- unaffected 6.17.8 – ≤ 6.17.*
- unaffected 6.18 – ≤ *
References
6
- https://git.kernel.org/stable/c/39c2c1a2773aaf73e56906e5ef670114eb2d354f (opens in a new tab)
- https://git.kernel.org/stable/c/4ac18f0e6a6d599ca751c4cd98e522afc8e3d4eb (opens in a new tab)
- https://git.kernel.org/stable/c/468f78276a37f4c6499385a4ce28f4f57be6655d (opens in a new tab)
- https://git.kernel.org/stable/c/c079d42f70109512eee49123a843be91d8fa133f (opens in a new tab)
- https://git.kernel.org/stable/c/de89d19f4f30d9a8de87b9d08c1bd35cb70576d8 (opens in a new tab)
- https://git.kernel.org/stable/c/a1f3058930745d2b938b6b4f5bd9630dc74b26b7 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-201622 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-40323)Record last updated .