CVE-2026-31590
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Drop WARN on large size for KVM_MEMORY_ENCRYPT_REG_REGION Drop the WARN in sev_pin_memory() on npages overflowing an int, as the WARN is comically trivially to trigger from userspace, e.g. by doing: struct kvm_enc_region range = { .addr = 0, .size = -1ul, }; __vm_ioctl(vm, KVM_MEMORY_ENCRYPT_REG_REGION, &range); Note, the checks in sev_mem_enc_register_region() that presumably exist to verify the incoming address+size are completely worthless, as both "addr" and "size" are u64s and SEV is 64-bit only, i.e. they _can't_ be greater than ULONG_MAX. That wart will be cleaned up in the near future. if (range->addr > ULONG_MAX || range->size > ULONG_MAX) return -EINVAL; Opportunistically add a comment to explain why the code calculates the number of pages the "hard" way, e.g. instead of just shifting @ulen.
EPSS 0.02% · 3.4th percentile
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | *, 6.18.24, 6.19.14 |
| linux | linux_kernel | 0, 0, 0 |
Timeline
- Apr 24, 2026 CVE Published
- Apr 24, 2026 Security Advisory
- Apr 27, 2026 Security Advisory
- May 18, 2026 EPSS Score
- May 19, 2026 EPSS Score
- May 20, 2026 EPSS Score
- May 21, 2026 EPSS Score
- May 22, 2026 EPSS Score
- May 23, 2026 EPSS Score
- May 24, 2026 EPSS Score
- May 25, 2026 EPSS Score
- May 26, 2026 EPSS Score
References
- https://git.kernel.org/stable/c/ab423e5892826202a660b5ac85d1125b0e8301a5 url
- https://git.kernel.org/stable/c/28cc13ca20431b127d42d84ba10898d03e2c8267 url
- https://git.kernel.org/stable/c/c29ff288a2d97a6f4640a498a367cf0eb91312eb url
- https://git.kernel.org/stable/c/1cba4dcd795daf6d257122779fb6a349edf03914 url
- https://nvd.nist.gov/vuln/detail/CVE-2026-31590 advisory
- https://lists.debian.org/debian-security-announce/2026/msg00154.html advisory
- https://lists.debian.org/debian-security-announce/2026/msg00148.html advisory