CVE-2025-8860
Qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
- Published
- Updated
- Reserved
- Assigned by
- fedora
Description
A flaw was found in QEMU in the uefi-vars virtual device. When the guest writes to register UEFI_VARS_REG_BUFFER_SIZE, the .write callback `uefi_vars_write` is invoked. The function allocates a heap buffer without zeroing the memory, leaving the buffer filled with residual data from prior allocations. When the guest later reads from register UEFI_VARS_REG_PIO_BUFFER_TRANSFER, the .read callback `uefi_vars_read` returns leftover metadata or other sensitive process memory from the previously allocated buffer, leading to an information disclosure vulnerability.
Timeline
ID reserved
By fedora
- 6 months later
· 6 months later
Published
- 1 day later
· 1 day 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 |
|---|---|---|---|
| fedoraCNA (assigner) | 3.1 | Low3.3 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
| NVDNVD · Deferred | 3.1 | Low3.3 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.17% · top 94% of all CVEs (7 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: Low 3.3.
Weakness
Affected products
qemu
- affected 10.0.0 – < 10.1.0
Red Hat · Red Hat Enterprise Linux 10
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 6
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 8
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 8 Advanced Virtualization
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 8 Advanced Virtualization
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 9
All versions: unaffected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: unaffected
References (2)
- https://access.redhat.com/security/cve/CVE-2025-8860 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2387588 (opens in a new tab)issue-trackingx_refsource_REDHAT
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)
- 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://trackcve.app/cve/CVE-2025-8860)Record last updated .