CVE-2025-8860
Publication date 20 August 2025
Last updated 26 August 2025
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| qemu | 25.04 plucky |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
Notes
mdeslaur
Per Debian, introduced with: https://gitlab.com/qemu-project/qemu/-/commit/90ca4e03c27dc8ac821a2e1686e705ae9a93d301