Description
snap-confine as included in snapd before 2.39 did not guard against symlink races when performing the chdir() to the current working directory of the calling user, aka a "cwd restore permission bypass."
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | snapd | 2.40-1 | — |
| Debian 13 | snapd | 2.40-1 | — |
| Debian 12 | snapd | 2.40-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | snapd | 2.39.2+18.04 | — |
| Ubuntu 16.04 LTS | snapd | 2.39.2ubuntu0.2 | — |