KVM: x86: Mark target gfn of emulated atomic instruction as dirty
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-401.
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Mark target gfn of emulated atomic instruction as dirty When emulating an atomic access on behalf of the guest, mark the target gfn dirty if the CMPXCHG by KVM is attempted and doesn't fault. This fixes a bug where KVM effectively corrupts guest memory during live migration by writing to guest memory without informing userspace that the page is dirty. Marking the page dirty got unintentionally dropped when KVM's emulated CMPXCHG was converted to do a user access. Before that, KVM explicitly mapped the guest page into kernel memory, and marked the page dirty during the unmap phase. Mark the page dirty even if the CMPXCHG fails, as the old data is written back on failure, i.e. the page is still written. The value written is guaranteed to be the same because the operation is atomic, but KVM's ABI is that all writes are dirty logged regardless of the value written. And more importantly, that's what KVM did before the buggy commit. Huge kudos to the folks on the Cc list (and many others), who did all the actual work of triaging and debugging. base-commit: 6769ea8da8a93ed4630f1ce64df6aafcaabfce64
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.15.58 to before 5.15.154; 5.17.13 to before 5.18; 5.18.2 to before 5.19 | 5.15.154, 5.18, 5.19 | Patch available | CNA |
| Linux | Linux | 5.19 and later | 5.15.154, 6.1.84, 6.6.24, 6.7.12, 6.8 | Patch available | CNA |
- Linux VendorLinux Affected 5.15.58 to before 5.15.154; 5.17.13 to before 5.18; 5.18.2 to before 5.19 Fixed in 5.15.154, 5.18, 5.19 Patch available CNA
- Linux VendorLinux Affected 5.19 and later Fixed in 5.15.154, 6.1.84, 6.6.24, 6.7.12, 6.8 Patch available CNA
CPE configurations NVD · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.15.58 to before 5.15.154; 5.17.13 to before 5.18; 5.18.2 to before 6.1.84; 6.2 to before 6.6.24; 6.7 to before 6.7.12 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:* | 6.8 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:* | 6.8 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:* | 6.8 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:* | 6.8 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:* | 6.8 rc5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc6:*:*:*:*:*:* | 6.8 rc6 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.8:rc7:*:*:*:*:*:* | 6.8 rc7 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.15.58 to before 5.15.154; 5.17.13 to before 5.18; 5.18.2 to before 6.1.84; 6.2 to before 6.6.24; 6.7 to before 6.7.12 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:* Versions 6.8 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:* Versions 6.8 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:* Versions 6.8 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:* Versions 6.8 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:* Versions 6.8 rc5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc6:*:*:*:*:*:* Versions 6.8 rc6 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.8:rc7:*:*:*:*:*:* Versions 6.8 rc7 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.15.154, 5.18, 5.19
- Fix · CNA Linux (Linux) Fixed in 5.15.154, 6.1.84, 6.6.24, 6.7.12, 6.8
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
Not affected: 2 products
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2024-35804
- 2026-10-03 Alias added: GHSA-x3cp-9cgr-m6gc
References
Patch 5
- https://git.kernel.org/stable/c/a9bd6bb6f02bf7132c1ab192ba62bbfa52df7d66
- https://git.kernel.org/stable/c/726374dde5d608b15b9756bd52b6fc283fda7a06
- https://git.kernel.org/stable/c/9d1b22e573a3789ed1f32033ee709106993ba551
- https://git.kernel.org/stable/c/225d587a073584946c05c9b7651d637bd45c0c71
- https://git.kernel.org/stable/c/910c57dfa4d113aae6571c2a8b9ae8c430975902
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2024-35804 · CVE Program
- CVE-2024-35804 · NVD
- FIRST EPSS
- GHSA-x3cp-9cgr-m6gc · GitHub Advisory Database · CC BY 4.0
- CVE-2024-35804 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences