| Name | CVE-2019-15847 |
| Description | The POWER9 backend in GNU Compiler Collection (GCC) before version 10 could optimize multiple calls of the __builtin_darn intrinsic into a single call, thus reducing the entropy of the random number generator. This occurred because a volatile operation was not specified. For example, within a single execution of a program, the output of every __builtin_darn() call may be the same. |
| 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 |
|---|
| gcc-7 (PTS) | buster | 7.4.0-6 | vulnerable |
| gcc-8 (PTS) | buster | 8.3.0-6 | vulnerable |
| gcc-9 (PTS) | bullseye | 9.3.0-22 | fixed |
| sid | 9.5.0-6 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| gcc-7 | source | (unstable) | 7.4.0-12 | | | |
| gcc-8 | source | (unstable) | 8.3.0-22 | | | |
| gcc-9 | source | (unstable) | 9.2.1-7 | low | | |
Notes
[buster] - gcc-7 <ignored> (minor issue, affects only POWER9 binaries)
[buster] - gcc-8 <ignored> (minor issue, affects only POWER9 binaries)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91481