CVE-2025-21976fbdev: hyperv_fb: Allow graceful removal of framebuffer
- 7.8HighCVSS base score
- 0.26%Exploitation in 30 daysEPSS · top 83% 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: fbdev: hyperv_fb: Allow graceful removal of framebuffer When a Hyper-V framebuffer device is unbind, hyperv_fb driver tries to release the framebuffer forcefully. If this framebuffer is in use it produce the following WARN and hence this framebuffer is never released. [ 44.111220] WARNING: CPU: 35 PID: 1882 at drivers/video/fbdev/core/fb_info.c:70 framebuffer_release+0x2c/0x40 < snip > [ 44.111289] Call Trace: [ 44.111290] <TASK> [ 44.111291] ? show_regs+0x6c/0x80 [ 44.111295] ? __warn+0x8d/0x150 [ 44.111298] ? framebuffer_release+0x2c/0x40 [ 44.111300] ? report_bug+0x182/0x1b0 [ 44.111303] ? handle_bug+0x6e/0xb0 [ 44.111306] ? exc_invalid_op+0x18/0x80 [ 44.111308] ? asm_exc_invalid_op+0x1b/0x20 [ 44.111311] ? framebuffer_release+0x2c/0x40 [ 44.111313] ? hvfb_remove+0x86/0xa0 [hyperv_fb] [ 44.111315] vmbus_remove+0x24/0x40 [hv_vmbus] [ 44.111323] device_remove+0x40/0x80 [ 44.111325] device_release_driver_internal+0x20b/0x270 [ 44.111327] ? bus_find_device+0xb3/0xf0 Fix this by moving the release of framebuffer and assosiated memory to fb_ops.fb_destroy function, so that framebuffer framework handles it gracefully. While we fix this, also replace manual registrations/unregistration of framebuffer with devm_register_framebuffer.
Timeline
ID reserved
By Linux
- 3 months later
· 3 months later
Published
- 19 months later
· 19 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 · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.26% · top 83% of all CVEs (13 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 68a2d20b79b105f02dcbc52c211d7e62f98996b7 – < b1a86a5ab0d44160534f495a3630646092d98e27
- affected 68a2d20b79b105f02dcbc52c211d7e62f98996b7 – < 4545e2aa121aea304d33903099c03e29ed4fe50a
- affected 68a2d20b79b105f02dcbc52c211d7e62f98996b7 – < a7b583dc99c6cf4a96877017be1d08247e1ef2c7
- affected 68a2d20b79b105f02dcbc52c211d7e62f98996b7 – < ea2f45ab0e53b255f72c85ccd99e2b394fc5fceb
- affected 3.10
- unaffected < 3.10
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.20 – ≤ 6.12.*
- unaffected 6.13.8 – ≤ 6.13.*
- unaffected 6.14 – ≤ *
References
References4
- https://git.kernel.org/stable/c/b1a86a5ab0d44160534f495a3630646092d98e27 (opens in a new tab)
- https://git.kernel.org/stable/c/4545e2aa121aea304d33903099c03e29ed4fe50a (opens in a new tab)
- https://git.kernel.org/stable/c/a7b583dc99c6cf4a96877017be1d08247e1ef2c7 (opens in a new tab)
- https://git.kernel.org/stable/c/ea2f45ab0e53b255f72c85ccd99e2b394fc5fceb (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-2025-9344 (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-2025-21976)Record last updated .