Answer in brief
CVE-2026-31590 records a Unknown severity vulnerability in KVM: SEV: Drop WARN on large size for KVM_MEMORY_ENCRYPT_REG_REGION. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <6a8e3c82122737529b25ef2a048fbcc569d8c055 || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <a703933bcfa5cc76ca10e2048464600e74136099 || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <abcd43ff579abd0a654bb4636086e78819dd5f4c || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <b670833749ffd8681361db2bb047c6f2e3075f3a || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <ab423e5892826202a660b5ac85d1125b0e8301a5 || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <28cc13ca20431b127d42d84ba10898d03e2c8267 || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <c29ff288a2d97a6f4640a498a367cf0eb91312eb || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <1cba4dcd795daf6d257122779fb6a349edf03914 || >=78824fabc72e5e37d51e6e567fde70a4fc41a6d7 <8acffeef5ef720c35e513e322ab08e32683f32f2 | 6a8e3c82122737529b25ef2a048fbcc569d8c055, a703933bcfa5cc76ca10e2048464600e74136099, abcd43ff579abd0a654bb4636086e78819dd5f4c, b670833749ffd8681361db2bb047c6f2e3075f3a, ab423e5892826202a660b5ac85d1125b0e8301a5, 28cc13ca20431b127d42d84ba10898d03e2c8267, c29ff288a2d97a6f4640a498a367cf0eb91312eb, 1cba4dcd795daf6d257122779fb6a349edf03914, 8acffeef5ef720c35e513e322ab08e32683f32f2 |
| Linux/Linuxgeneric | 5.9 | Not reported |
Published upstream
Apr 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 6, 2026
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.
Quoted source text, attributed separately from HOL analysis.