Use-after-free in Linux kernel - CVE-2026-90277

Vulnerability details

The vulnerability allows a local user to trigger a use-after-free condition.

The vulnerability exists due to a use-after-free in llbitmap_create() when bitmap creation fails while bitmap statistics are being collected. A local user can trigger a failed bitmap creation while a mutex-protected reader accesses bitmap statistics to trigger a use-after-free condition.

Affected software

How to mitigate CVE-2026-90277

External References

• https://git.kernel.org/stable/c/2116c2f0a0e547615886900e2ed8c529c016499b
• https://git.kernel.org/stable/c/2f0722435ce3a844dbb66b9bb0a18229dcc8739c
• https://git.kernel.org/stable/c/930cc4f1af5a1afcd545a6ba00e38921ff8401e0

Related Security Bulletins

• Use-after-free in Linux kernel md driver