CVE-2026-93045

Summary

In the Linux kernel, the following vulnerability has been resolved:

bpf: Reject arena frees below the arena base

bpf_arena_free_pages() accepts scalar arena addresses. The runtime masks the address to the low 32 bits and reconstructs a full user address from the arena base before returning the range to the arena free tree.

When the scalar value is below the low 32 bits of the arena base, full_uaddr falls below user_vm_start. The existing upper-end clipping then turns this into an out-of-range free-tree offset. A later allocation can reuse that offset and return an address below the arena mapping.

Reject such frees before computing the clipped range.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux317460317a02a1af512697e6e964298dedd8a163 < 90453eaf8f14e7be0ab03983f2a93aeb6b990a58affected
LinuxLinux317460317a02a1af512697e6e964298dedd8a163 < a968dffa5ab3c74d2ebb3a6233bf8b843f0bfc20affected
LinuxLinux317460317a02a1af512697e6e964298dedd8a163 < 8a08635656037aee9c12231ed384449c4ffb1a93affected
LinuxLinux317460317a02a1af512697e6e964298dedd8a163 < b5a71cb2db6d84ac0042549dcec266b18429d41eaffected
LinuxLinux6.9affected
LinuxLinux0 < 6.9unaffected
LinuxLinux6.12.110 <= 6.12.*unaffected
LinuxLinux6.18.52 <= 6.18.*unaffected
LinuxLinux7.2.6 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References