| Name | CVE-2021-4145 |
| Description | A NULL pointer dereference issue was found in the block mirror layer of QEMU in versions prior to 6.2.0. The `self` pointer is dereferenced in mirror_wait_on_conflicts() without ensuring that it's not NULL. A malicious unprivileged user within the guest could use this flaw to crash the QEMU process on the host when writing data reaches the threshold of mirroring node. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| qemu (PTS) | bullseye | 1:5.2+dfsg-11+deb11u3 | fixed |
| bullseye (security) | 1:5.2+dfsg-11+deb11u2 | fixed |
| bookworm | 1:7.2+dfsg-7+deb12u7 | fixed |
| sid, trixie | 1:9.2.0+ds-2 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| qemu | source | stretch | (not affected) | | | |
| qemu | source | buster | (not affected) | | | |
| qemu | source | bullseye | (not affected) | | | |
| qemu | source | (unstable) | 1:6.2+dfsg-1 | | | |
Notes
[bullseye] - qemu <not-affected> (Vulnerable code introduced later)
[buster] - qemu <not-affected> (Vulnerable code introduced later)
[stretch] - qemu <not-affected> (Vulnerable code introduced later)
Introduced by: https://gitlab.com/qemu-project/qemu/-/commit/d44dae1a7cf782ec9235746ebb0e6c1a20dd7288 (v6.1.0-rc0)
Fixed by: https://gitlab.com/qemu-project/qemu/-/commit/66fed30c9cd11854fc878a4eceb507e915d7c9cd (v6.2.0-rc0)