CVE-2025-8860
published 2026-02-18CVE-2025-8860: 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…
PriorityP413low3.3CVSS 3.1
AVLACLPRLUINSUCLINAN
EPSS
0.17%
5.6th percentile
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.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | qemu | < qemu 1:10.0.3+ds-4 (forky) | qemu 1:10.0.3+ds-4 (forky) |
| qemu | qemu | >= 0 < 1:10.0.3+ds-4 | 1:10.0.3+ds-4 |
| qemu | qemu | >= 0 < 1:10.0.3+ds-4 | 1:10.0.3+ds-4 |
CVSS provenance
nvdv3.13.3LOWCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
osv3.3LOW
vendor_debian3.3LOW
vendor_redhat3.3LOW
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Red Hat
qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
vendor_redhat·2025-08-11·CVSS 3.3
CVE-2025-8860 [LOW] CWE-212 qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
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.
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_va
Debian
CVE-2025-8860: qemu - A flaw was found in QEMU in the uefi-vars virtual device. When the guest writes ...
vendor_debian·2025·CVSS 3.3
CVE-2025-8860 [LOW] CVE-2025-8860: qemu - A flaw was found in QEMU in the uefi-vars virtual device. When the guest writes ...
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.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved (fixed in 1:10.0.3+ds-4)
sid: resolved (fixed in 1:10.0.3+ds-4)
trixie: resolved (fixed in 1:10.0.3+ds-4)
GHSA
GHSA-xrj7-v4x4-74hr: A flaw was found in QEMU in the uefi-vars virtual device
ghsa_unreviewed·2026-02-18
CVE-2025-8860 [LOW] CWE-212 GHSA-xrj7-v4x4-74hr: A flaw was found in QEMU in the uefi-vars virtual device
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.
OSV
CVE-2025-8860: A flaw was found in QEMU in the uefi-vars virtual device
osv·2026-02-18·CVSS 3.3
CVE-2025-8860 [LOW] CVE-2025-8860: A flaw was found in QEMU in the uefi-vars virtual device
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.
OSV
CVE-2025-8860: When the guest writes to register UEFI_VARS_REG_BUFFER_SIZE, the
osv·2025-08-20·CVSS 3.3
CVE-2025-8860 [LOW] CVE-2025-8860: When the guest writes to register UEFI_VARS_REG_BUFFER_SIZE, the
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.
No detection rules found.
No public exploits indexed.
Wiz
CVE-2025-8860 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 3.3
CVE-2025-8860 [LOW] CVE-2025-8860 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2025-8860 :
Wolfi vulnerability analysis and mitigation
uefi_vars_write
uefi_vars_read
Source : NVD
## 3.3
Score
Published February 18, 2026
Severity LOW
CNA Score 3.3
Affected Technologies
Wolfi
Chainguard
Has Public Exploit No
Has CISA KEV Exploit No
CISA KEV Release Date N/A
CISA KEV Due Date N/A
Exploitation Probability Percentile (EPSS) 0.5
Exploitation Probability (EPSS) N/A
Affected packages and libraries
qemu-img
qemu-kvm
Sources
NVD
Chainguard No Fix Added at: Feb 19, 2026
Debian 11, 12 No Fix Added at: Aug 13, 2025
Debian 13 Severity MEDIUM Has Fix Added at: Aug 13, 2025
Debian 14 Severity LOW Has Fix Added at: Aug 13, 2025
Red Hat 10 Severity LOW No Fix Added at: Aug 12, 2025
Windows Severity LOW Has Fix Added at: Feb 19, 2026
Wolfi No Fix
Bugzilla
CVE-2025-8860 qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
bugzilla·2025-08-11·CVSS 3.3
CVE-2025-8860 [LOW] CVE-2025-8860 qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
CVE-2025-8860 qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
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.
Discussion:
Upstream fix:
https://gitlab.com/qemu-project/qemu/-/commit/f757d9d90d19b914d4023663bfc4da73bbbf007e
2026-02-18
Published