In rsync 3.0.1 through 3.4.1, receive_xattr relies on an untrusted length value during a qsort call, leading to a receiver use-after-free. The victim must run rsync with -X (aka --xattrs). On Linux, many (but not all) common configurations are vulnerable. Non-Linux platforms are more widely vulnerable.
3.1.3-63.1.3-83.1.3-8ubuntu0.13.1.3-8ubuntu0.23.1.3-8ubuntu0.33.1.3-8ubuntu0.43.1.3-8ubuntu0.53.1.3-8ubuntu0.73.1.3-8ubuntu0.83.1.3-8ubuntu0.93.2.7-0ubuntu0.22.04.63.2.7-1ubuntu1.43.4.1+ds1-5ubuntu1.23.4.1+ds1-7ubuntu0.23.0.9-4ubuntu13.1.0-23.1.0-2ubuntu0.13.1.0-2ubuntu0.23.1.0-2ubuntu0.33.1.0-2ubuntu0.43.1.0-2ubuntu0.4+esm13.1.0-2ubuntu0.4+esm23.1.1-33.1.1-3ubuntu13.1.1-3ubuntu1.13.1.1-3ubuntu1.23.1.1-3ubuntu1.33.1.1-3ubuntu1.3+esm13.1.1-3ubuntu1.3+esm23.1.1-3ubuntu1.3+esm33.1.1-3ubuntu1.3+esm43.1.2-23.1.2-2.13.1.2-2.1ubuntu13.1.2-2.1ubuntu1.13.1.2-2.1ubuntu1.23.1.2-2.1ubuntu1.33.1.2-2.1ubuntu1.43.1.2-2.1ubuntu1.53.1.2-2.1ubuntu1.63.1.2-2.1ubuntu1.6+esm1+1 moreExploitability
AV:NAC:LPR:LUI:NScope
S:CImpact
C:LI:LA:LCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L