| Name | CVE-2020-6096 |
| Description | An exploitable signed comparison vulnerability exists in the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. Calling memcpy() (on ARMv7 targets that utilize the GNU glibc implementation) with a negative value for the 'num' parameter results in a signed comparison vulnerability. If an attacker underflows the 'num' parameter to memcpy(), this vulnerability could lead to undefined behavior such as writing to out-of-bounds memory and potentially remote code execution. Furthermore, this memcpy() implementation allows for program execution to continue in scenarios where a segmentation fault or crash should have occurred. The dangers occur in that subsequent execution and iterations of this code will be executed with this corrupted data. |
| 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-3152-1 |
| Debian Bugs | 961452 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| glibc (PTS) | jessie, jessie (lts) | 2.19-18+deb8u14 | fixed |
| stretch (security) | 2.24-11+deb9u1 | vulnerable |
| stretch (lts), stretch | 2.24-11+deb9u7 | vulnerable |
| buster (security), buster, buster (lts) | 2.28-10+deb10u4 | fixed |
| bullseye | 2.31-13+deb11u11 | fixed |
| bullseye (security) | 2.31-13+deb11u10 | fixed |
| bookworm | 2.36-9+deb12u9 | fixed |
| bookworm (security) | 2.36-9+deb12u7 | fixed |
| sid, trixie | 2.40-4 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| glibc | source | jessie | (not affected) | | | |
| glibc | source | buster | 2.28-10+deb10u2 | | DLA-3152-1 | |
| glibc | source | (unstable) | 2.31-2 | low | | 961452 |
Notes
[jessie] - glibc <not-affected> (Vulnerable code not present)
https://sourceware.org/bugzilla/show_bug.cgi?id=25620
https://talosintelligence.com/vulnerability_reports/TALOS-2020-1019
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=beea361050728138b82c57dda0c4810402d342b9
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=79a4fa341b8a89cb03f84564fd72abaa1a2db394
[stretch] - glibc <ignored> (arm-only memcpy with large size parameter, porting assembly code required)