CVE-2026-31592
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Protect *all* of sev_mem_enc_register_region() with kvm->lock Take and hold kvm->lock for before checking sev_guest() in sev_mem_enc_register_region(), as sev_guest() isn't stable unless kvm->lock is held (or KVM can guarantee KVM_SEV_INIT{2} has completed and can't rollack state). If KVM_SEV_INIT{2} fails, KVM can end up trying to add to a not-yet-initialized sev->regions_list, e.g. triggering a #GP Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 110 UID: 0 PID: 72717 Comm: syz.15.11462 Tainted: G U W O 6.16.0-smp-DEV #1 NONE Tainted: [U]=USER, [W]=WARN, [O]=OOT_MODULE Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.52.0-0 10/28/2024 RIP: 0010:sev_mem_enc_register_region+0x3f0/0x4f0 ../include/linux/list.h:83 Code: <41> 80 3c 04 00 74 08 4c 89 ff e8 f1 c7 a2 00 49 39 ed 0f 84 c6 00 RSP: 0018:ffff88838647fbb8 EFLAGS: 00010256 RAX: dffffc0000000000 RBX: 1ffff92015cf1e0b RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000001000 RDI: ffff888367870000 RBP: ffffc900ae78f050 R08: ffffea000d9e0007 R09: 1ffffd4001b3c000 R10: dffffc0000000000 R11: fffff94001b3c001 R12: 0000000000000000 R13: ffff8982ab0bde00 R14: ffffc900ae78f058 R15: 0000000000000000 FS: 00007f34e9dc66c0(0000) GS:ffff89ee64d33000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe180adef98 CR3: 000000047210e000 CR4: 0000000000350ef0 Call Trace: <TASK> kvm_arch_vm_ioctl+0xa72/0x1240 ../arch/x86/kvm/x86.c:7371 kvm_vm_ioctl+0x649/0x990 ../virt/kvm/kvm_main.c:5363 __se_sys_ioctl+0x101/0x170 ../fs/ioctl.c:51 do_syscall_x64 ../arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x6f/0x1f0 ../arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f34e9f7e9a9 Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f34e9dc6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f34ea1a6080 RCX: 00007f34e9f7e9a9 RDX: 0000200000000280 RSI: 000000008010aebb RDI: 0000000000000007 RBP: 00007f34ea000d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f34ea1a6080 R15: 00007ffce77197a8 </TASK> with a syzlang reproducer that looks like: syz_kvm_add_vcpu$x86(0x0, &(0x7f0000000040)={0x0, &(0x7f0000000180)=ANY=[], 0x70}) (async) syz_kvm_add_vcpu$x86(0x0, &(0x7f0000000080)={0x0, &(0x7f0000000180)=ANY=[@ANYBLOB="..."], 0x4f}) (async) r0 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000200), 0x0, 0x0) r1 = ioctl$KVM_CREATE_VM(r0, 0xae01, 0x0) r2 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000240), 0x0, 0x0) r3 = ioctl$KVM_CREATE_VM(r2, 0xae01, 0x0) ioctl$KVM_SET_CLOCK(r3, 0xc008aeba, &(0x7f0000000040)={0x1, 0x8, 0x0, 0x5625e9b0}) (async) ioctl$KVM_SET_PIT2(r3, 0x8010aebb, &(0x7f0000000280)={[...], 0x5}) (async) ioctl$KVM_SET_PIT2(r1, 0x4070aea0, 0x0) (async) r4 = ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0) openat$kvm(0xffffffffffffff9c, 0x0, 0x0, 0x0) (async) ioctl$KVM_SET_USER_MEMORY_REGION(r4, 0x4020ae46, &(0x7f0000000400)={0x0, 0x0, 0x0, 0x2000, &(0x7f0000001000/0x2000)=nil}) (async) r5 = ioctl$KVM_CREATE_VCPU(r4, 0xae41, 0x2) close(r0) (async) openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x8000, 0x0) (async) ioctl$KVM_SET_GUEST_DEBUG(r5, 0x4048ae9b, &(0x7f0000000300)={0x4376ea830d46549b, 0x0, [0x46, 0x0, 0x0, 0x0, 0x0, 0x1000]}) (async) ioctl$KVM_RUN(r5, 0xae80, 0x0) Opportunistically use guard() to avoid having to define a new error label and goto usage.
View original CVE JSON
{
"id": "CVE-2026-31592",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-04-24T15:16:36.667",
"lastModified": "2026-10-30T13:18:41.383",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Protect *all* of sev_mem_enc_register_region() with kvm->lock\n\nTake and hold kvm->lock for before checking sev_guest() in\nsev_mem_enc_register_region(), as sev_guest() isn't stable unless kvm->lock\nis held (or KVM can guarantee KVM_SEV_INIT{2} has completed and can't\nrollack state). If KVM_SEV_INIT{2} fails, KVM can end up trying to add to\na not-yet-initialized sev->regions_list, e.g. triggering a #GP\n\n Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI\n KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n CPU: 110 UID: 0 PID: 72717 Comm: syz.15.11462 Tainted: G U W O 6.16.0-smp-DEV #1 NONE\n Tainted: [U]=USER, [W]=WARN, [O]=OOT_MODULE\n Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.52.0-0 10/28/2024\n RIP: 0010:sev_mem_enc_register_region+0x3f0/0x4f0 ../include/linux/list.h:83\n Code: <41> 80 3c 04 00 74 08 4c 89 ff e8 f1 c7 a2 00 49 39 ed 0f 84 c6 00\n RSP: 0018:ffff88838647fbb8 EFLAGS: 00010256\n RAX: dffffc0000000000 RBX: 1ffff92015cf1e0b RCX: dffffc0000000000\n RDX: 0000000000000000 RSI: 0000000000001000 RDI: ffff888367870000\n RBP: ffffc900ae78f050 R08: ffffea000d9e0007 R09: 1ffffd4001b3c000\n R10: dffffc0000000000 R11: fffff94001b3c001 R12: 0000000000000000\n R13: ffff8982ab0bde00 R14: ffffc900ae78f058 R15: 0000000000000000\n FS: 00007f34e9dc66c0(0000) GS:ffff89ee64d33000(0000) knlGS:0000000000000000\n CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007fe180adef98 CR3: 000000047210e000 CR4: 0000000000350ef0\n Call Trace:\n <TASK>\n kvm_arch_vm_ioctl+0xa72/0x1240 ../arch/x86/kvm/x86.c:7371\n kvm_vm_ioctl+0x649/0x990 ../virt/kvm/kvm_main.c:5363\n __se_sys_ioctl+0x101/0x170 ../fs/ioctl.c:51\n do_syscall_x64 ../arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x6f/0x1f0 ../arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n RIP: 0033:0x7f34e9f7e9a9\n Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48\n RSP: 002b:00007f34e9dc6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010\n RAX: ffffffffffffffda RBX: 00007f34ea1a6080 RCX: 00007f34e9f7e9a9\n RDX: 0000200000000280 RSI: 000000008010aebb RDI: 0000000000000007\n RBP: 00007f34ea000d69 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\n R13: 0000000000000000 R14: 00007f34ea1a6080 R15: 00007ffce77197a8\n </TASK>\n\nwith a syzlang reproducer that looks like:\n\n syz_kvm_add_vcpu$x86(0x0, &(0x7f0000000040)={0x0, &(0x7f0000000180)=ANY=[], 0x70}) (async)\n syz_kvm_add_vcpu$x86(0x0, &(0x7f0000000080)={0x0, &(0x7f0000000180)=ANY=[@ANYBLOB=\"...\"], 0x4f}) (async)\n r0 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000200), 0x0, 0x0)\n r1 = ioctl$KVM_CREATE_VM(r0, 0xae01, 0x0)\n r2 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000240), 0x0, 0x0)\n r3 = ioctl$KVM_CREATE_VM(r2, 0xae01, 0x0)\n ioctl$KVM_SET_CLOCK(r3, 0xc008aeba, &(0x7f0000000040)={0x1, 0x8, 0x0, 0x5625e9b0}) (async)\n ioctl$KVM_SET_PIT2(r3, 0x8010aebb, &(0x7f0000000280)={[...], 0x5}) (async)\n ioctl$KVM_SET_PIT2(r1, 0x4070aea0, 0x0) (async)\n r4 = ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)\n openat$kvm(0xffffffffffffff9c, 0x0, 0x0, 0x0) (async)\n ioctl$KVM_SET_USER_MEMORY_REGION(r4, 0x4020ae46, &(0x7f0000000400)={0x0, 0x0, 0x0, 0x2000, &(0x7f0000001000/0x2000)=nil}) (async)\n r5 = ioctl$KVM_CREATE_VCPU(r4, 0xae41, 0x2)\n close(r0) (async)\n openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x8000, 0x0) (async)\n ioctl$KVM_SET_GUEST_DEBUG(r5, 0x4048ae9b, &(0x7f0000000300)={0x4376ea830d46549b, 0x0, [0x46, 0x0, 0x0, 0x0, 0x0, 0x1000]}) (async)\n ioctl$KVM_RUN(r5, 0xae80, 0x0)\n\nOpportunistically use guard() to avoid having to define a new error label\nand goto usage."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"arch/x86/kvm/svm/sev.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "1e80fdc09d121d8327cdf62eefbb5abadddca792",
"lessThan": "c506405f438b3e739fa43d509d367d1946ad9ffe",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "777a8ebd2da3529a455af022ed929408fdbb161f",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "25c85d5831201391fb920d51067c6d93cce55348",
"versionType": "git",
"status": "affected"
},
{
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"lessThan": "35a0963d361f98bba798fd15d229dcb166c04684",
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"status": "affected"
},
{
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"lessThan": "ab725ac3022469ecd4d7aa7d5646712e98b249d8",
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{
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"lessThan": "0ff93ff0ba82e9511770e175fa50682a1ab14fb6",
"versionType": "git",
"status": "affected"
},
{
"version": "1e80fdc09d121d8327cdf62eefbb5abadddca792",
"lessThan": "b6408b6cec5df76a165575777800ef2aba12b109",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"arch/x86/kvm/svm/sev.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "4.16",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.16",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.191",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.160",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.114",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.24",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.19.14",
"lessThanOrEqual": "6.19.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.0.1",
"lessThanOrEqual": "7.0.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-476"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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"matchCriteriaId": "4B2F764F-84E7-49EF-8E7A-C811DB6A0345"
},
{
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"matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB"
},
{
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}
]
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"references": [
{
"url": "https://git.kernel.org/stable/c/0ff93ff0ba82e9511770e175fa50682a1ab14fb6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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}