| Name | CVE-2021-34556 |
| Description | In the Linux kernel through 5.13.7, an unprivileged BPF program can obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel attack because the protection mechanism neglects the possibility of uninitialized memory locations on the BPF stack. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-2785-1 |
Vulnerable and fixed packages
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 | 6.1.66-1 | 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 | buster | 4.19.208-1 | | | |
| linux | source | (unstable) | 5.10.46-4 | | | |
| linux-4.19 | source | stretch | 4.19.208-1~deb9u1 | | DLA-2785-1 | |
Notes
[stretch] - linux <ignored> (Too risky to backport, and mitigated by default)
https://www.openwall.com/lists/oss-security/2021/08/01/3