/bin/login in shadow 4.0.18.1 in Debian GNU/Linux, and probably other Linux distributions, allows local users in the utmp group to overwrite arbitrary files via a symlink attack on a temporary file referenced in a line (aka ut_line) field in a utmp entry.
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
Name | Vendor | Start Version | End Version |
---|---|---|---|
Shadow | Debian | 4.0.18.1 (including) | 4.0.18.1 (including) |
Shadow | Ubuntu | dapper | * |
Shadow | Ubuntu | devel | * |
Shadow | Ubuntu | gutsy | * |
Shadow | Ubuntu | hardy | * |
Shadow | Ubuntu | intrepid | * |
Shadow | Ubuntu | upstream | * |