| Name | CVE-2021-20194 |
| Description | There is a vulnerability in the linux kernel versions higher than 5.2 (if kernel compiled with config params CONFIG_BPF_SYSCALL=y , CONFIG_BPF=y , CONFIG_CGROUPS=y , CONFIG_CGROUP_BPF=y , CONFIG_HARDENED_USERCOPY not set, and BPF hook to getsockopt is registered). As result of BPF execution, the local user can trigger bug in __cgroup_bpf_run_filter_getsockopt() function that can lead to heap overflow (because of non-hardened usercopy). The impact of attack could be deny of service or possibly privileges escalation. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| linux (PTS) | buster | 4.19.249-2 | fixed |
| buster (security) | 4.19.289-2 | fixed | |
| bullseye | 5.10.197-1 | fixed | |
| bullseye (security) | 5.10.191-1 | fixed | |
| bookworm | 6.1.55-1 | fixed | |
| bookworm (security) | 6.1.52-1 | fixed | |
| sid, trixie | 6.5.13-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| linux | source | stretch | (not affected) | |||
| linux | source | buster | (not affected) | |||
| linux | source | (unstable) | 5.10.19-1 |
[buster] - linux <not-affected> (Vulnerable code not present)
[stretch] - linux <not-affected> (Vulnerable code not present)
https://bugzilla.redhat.com/show_bug.cgi?id=1912683
https://patchwork.kernel.org/project/netdevbpf/patch/20210122164232.61770-1-loris.reiff@liblor.ch/#23921223