Qemu-kvm: uefi-vars: information disclosure vulnerability in uefi_vars_write callback
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 10.1.0
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
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
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- qemu
From 10.0.0 · fixed in 10.1.0
- qemu-kvm
Version range not reported
- qemu-kvm
Version range not reported
- qemu-kvm
Version range not reported
- qemu-kvm-ma
Version range not reported
- virt:rhel/qemu-kvm
Version range not reported
- virt:8.2/qemu-kvm
Version range not reported
- virt:av/qemu-kvm
Version range not reported
- qemu-kvm
Version range not reported
- rhcos
Version range not reported