CVE-2025-21821: Linux kernel · fbdev: omap: use threaded IRQ for LCD DMA
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 30 Oct 2026, 01:14 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Feb 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
A fix is available that switches the LCD DMA interrupt handling to use a threaded IRQ, which stabilizes the system and prevents the crash. Users should update to a Linux kernel version that includes this fix. Patch status is not explicitly confirmed in the input, so verify with the vendor or kernel source for the fixed version.
Description
A vulnerability in the Linux kernel's framebuffer device driver for OMAP platforms caused system crashes on devices like the Nokia 770 when using touchscreen and framebuffer simultaneously. The issue was due to improper handling of LCD DMA interrupts, leading to scheduling in atomic context and kernel BUGs. The problem was resolved by switching to a threaded IRQ for LCD DMA, stabilizing the system.
References
- nvd.nist.gov/vuln/detail/CVE-2025-21821 (opens in a new tab)
- git.kernel.org/stable/c/7bbbd311dd503653a2cc86d9226740883051dc92 (opens in a new tab)
- git.kernel.org/stable/c/8392ea100f0b86c234c739c6662f39f0ccc0cefd (opens in a new tab)
- git.kernel.org/stable/c/aa8e22cbedeb626f2a6bda0aea362353d627cd0a (opens in a new tab)
- git.kernel.org/stable/c/e4b6b665df815b4841e71b72f06446884e8aad40 (opens in a new tab)
- git.kernel.org/stable/c/fb6a5edb60921887d7d10619fcdcbee9759552cb (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/03/msg00028.html (opens in a new tab)