CVE-2024-35804KVM: x86: Mark target gfn of emulated atomic instruction as dirty
- 8.8HighCVSS base score
- 0.24%Exploitation in 30 daysEPSS · top 85% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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
Timeline
ID reserved
By Linux
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.24% · top 85% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Affected products
- affected d97c0667c1e61ded6639117b4b9584a9c12b7e66 – < a9bd6bb6f02bf7132c1ab192ba62bbfa52df7d66
- affected 1c2361f667f3648855ceae25f1332c18413fdb9f – < 726374dde5d608b15b9756bd52b6fc283fda7a06
- affected 1c2361f667f3648855ceae25f1332c18413fdb9f – < 9d1b22e573a3789ed1f32033ee709106993ba551
- affected 1c2361f667f3648855ceae25f1332c18413fdb9f – < 225d587a073584946c05c9b7651d637bd45c0c71
- affected 1c2361f667f3648855ceae25f1332c18413fdb9f – < 910c57dfa4d113aae6571c2a8b9ae8c430975902
- affected b0f294103f4cf733e23d3f0c4e5fd58e42998921
- affected e964665cc7ca13a16992b205fce63554b9efc78b
- affected 5.15.58 – < 5.15.154
- affected 5.17.13 – < 5.18
- affected 5.18.2 – < 5.19
- affected 5.19
- unaffected < 5.19
- unaffected 5.15.154 – ≤ 5.15.*
- unaffected 6.1.84 – ≤ 6.1.*
- unaffected 6.6.24 – ≤ 6.6.*
- unaffected 6.7.12 – ≤ 6.7.*
- unaffected 6.8 – ≤ *
References
References5
- https://git.kernel.org/stable/c/a9bd6bb6f02bf7132c1ab192ba62bbfa52df7d66 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/726374dde5d608b15b9756bd52b6fc283fda7a06 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/9d1b22e573a3789ed1f32033ee709106993ba551 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/225d587a073584946c05c9b7651d637bd45c0c71 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/910c57dfa4d113aae6571c2a8b9ae8c430975902 (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2024-35796 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2024-35804)Record last updated .