Microsoft security update for CVE-2025-21976
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21976. This page also shows what EchelonGraph holds for CVE-2025-21976, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products26
- azl3 kernel 6.6.104.2-4 on Azure Linux 3.0
- azl3 kernel 6.6.112.1-2 on Azure Linux 3.0
- azl3 kernel 6.6.117.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.119.3-1 on Azure Linux 3.0
- azl3 kernel 6.6.119.3-3 on Azure Linux 3.0
- azl3 kernel 6.6.121.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.126.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.130.1-3 on Azure Linux 3.0
- azl3 kernel 6.6.134.1-2 on Azure Linux 3.0
- azl3 kernel 6.6.137.1-2 on Azure Linux 3.0
- azl3 kernel 6.6.138.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.139.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.141.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.143.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.144.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.145.2-1 on Azure Linux 3.0
- azl3 kernel 6.6.150.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.152.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.157.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.159.1-1 on Azure Linux 3.0
- azl3 kernel 6.6.161.1-1 on Azure Linux 3.0
- cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0
- cbl2 kernel 5.15.200.1-1 on CBL Mariner 2.0
- cbl2 kernel 5.15.202.1-1
- cbl2 kernel 5.15.202.1-1 on CBL Mariner 2.0
- cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0
✅ Updates Microsoft lists: 1 update
1 row: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | — |
🧭 EchelonGraph on CVE-2025-21976
- EchelonGraph score
- 5.5 MEDIUM
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
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.
Published by kernel.org, the CVE Numbering Authority that assigned CVE-2025-21976, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).