Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-98719— KVM: SEV: Nullify "have run CPUs" mask pointer when freeing it

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

在 Linux 内核中，以下漏洞已得到修复： KVM: SEV：在释放"have run CPUs"掩码指针时将其置空 在释放掩码时将 置空，特别是在 的错误处理路径中，这样 KVM 就不必隐式地依赖 来跟踪该掩码是否已被释放。正如 Sashiko 指出的那样，如果在 失败后， 中盲目地再次释放该掩码，会导致双重释放（double-free）问题。 将相关逻辑封装到一个辅助函数中，因为当 时， 是一个单元素数组，导致直接置空指针变得异常困难且怪异。我们刻意避免使用 ，因为当 cpumask 位于栈上时，它无法直接赋

AI Predicted 5.5 Difficulty: Hard EPSS 0.17% · P5

Possible ATT&CK Techniques 1 AI

T1068 · Exploitation for Privilege Escalation

Affected Version Matrix 5

VendorProduct Version RangeStatus
Linux Linux 6aef7cf800098749ff5d660222efaf6e01e98c09< b1de3ebf59507e0edacaa5cfa2225bc1869e1b63 affected
9784e5ca91b37b387f3f414af4340c54f7a63566< 0fbc7fec2242de6c3dcea6de55573c428e820173 affected
12c1f6e03f944e399bd2c88441dca5dc702b95a5< 8abbc76120a74bfba1851bd97528099d715e45c6 affected
6.18.55< 6.18.56 affected
7.2.9< 7.2.10 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-98719

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
KVM: SEV: Nullify "have run CPUs" mask pointer when freeing it
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Nullify "have run CPUs" mask pointer when freeing it Nullify have_run_cpus when freeing the mask, particularly in the error path of __sev_guest_init(), so that KVM doesn't have to subtly use sev->active to track whether or not the mask has been freed. As pointed out by Sashiko, blindly freeing the mask in sev_vm_destroy() results in a double-free if the mask is freed if __sev_guest_init() fails. Throw the logic in a helper as nullifying the pointer is frustratingly difficult and weird due to have_run_cpus being a single-entry array when CPUMASK_OFFSTACK=n. Deliberately don't use CPUMASK_VAR_NULL, as it's not directly assignable when the cpumask is on-stack, e.g. requires using a local variable and a memcpy(), which is beyond ridiculous. Furthermore, while clearing the on-stack bitmask is an unnecessary and arguably unwanted side effect, KVM absolutely relies on '0' being the "null" value given that the struct is zero-allocated. Opportunistically add an alloc() helper to pair with free(); there are just enough call sites to make doing so worthwhile.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 6aef7cf800098749ff5d660222efaf6e01e98c09 ~ b1de3ebf59507e0edacaa5cfa2225bc1869e1b63 -
Linux Linux 6.18.55 ~ 6.18.56 -

II. Public POCs for CVE-2026-98719

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-98719

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-98719 (3)

Same Patch Batch · Linux · 2026-10-18 · 435 CVEs total

CVE-2026-98720 KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified
CVE-2026-98733 Bluetooth: hci_core: Serialize fragmented ISO packet queueing
CVE-2026-98732 Bluetooth: btintel: fix buffer over-read in btintel_hw_error()
CVE-2026-98731 Bluetooth: btintel_pcie: fix plen overflow in btintel_pcie_recv_frame()
CVE-2026-98730 Bluetooth: btintel_pcie: reject oversized TX packets in send_frame()
CVE-2026-98729 x86/mm: Don't apply va_align to hugetlb mappings on AMD F15h
CVE-2026-98728 tpm: fix off-by-four bounds check in tpm2_get_random()
CVE-2026-98727 nvme-multipath: set BLK_FEAT_ZONED only after the zone info is known
CVE-2026-98726 nvme-multipath: fix underflow in ANA log bounds checks
CVE-2026-98725 nvmet-auth: fix out-of-bounds write in nvmet_auth_challenge()
CVE-2026-98724 nvmet: pci-epf: reject too-short SGL segments
CVE-2026-98723 nvmet: copy the hostid into the ctrl before creating PR pc_refs
CVE-2026-98722 mtd: block2mtd: Fix divide error when erase_size is zero
CVE-2026-98721 mtd: rawnand: cadence: Initialize IRQ state before requesting IRQ
CVE-2026-98707 wifi: mac80211: shut down RX BA session timer on teardown
CVE-2026-98711 wifi: cw1200: fix TX padding OOB read leaking heap data to device
CVE-2026-98710 wifi: iwlegacy: 3945: free EEPROM data on remove
CVE-2026-98709 wifi: mac80211: count only matching reservations in reserved switch
CVE-2026-98712 KVM: arm64: vgic: Take a refcount on IRQs referenced by last_lr_irq
CVE-2026-98708 wifi: mac80211: keep paired old chanctx alive

Showing top 20 of 435 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-98719

No comments yet

Leave a comment