Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-3945
Advisory Released Date: 2026-09-28
Advisory Updated Date: 2026-09-28
rsync before 3.5.0 contains an algorithmic complexity vulnerability in the hash_search() function that allows a remote attacker to cause a denial of service by delivering a carefully constructed file list. A sender can exploit the quadratic-time worst-case behavior in hash lookups to exhaust receiver CPU resources with a modest number of crafted entries, causing a sustained denial of service.
NOTE: https://download.samba.org/pub/rsync/NEWS#3.5.0 (CVE-2026-70453)
rsync 3.0.0 before 3.5.0 contains an out-of-bounds write vulnerability that allows attackers to corrupt memory by triggering HLINK_BUMP processing on file entries with the FLAG_HLINKED flag set while the hard-link preservation option is inactive. Attackers can exploit the missing F_SUM field in the file_struct layout to access memory past the end of the allocated structure, corrupting adjacent heap or stack data.
NOTE: https://download.samba.org/pub/rsync/NEWS#3.5.0 (CVE-2026-70458)
Affected Packages:
rsync
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update rsync or yum update --advisory ALAS2-2026-3945 to update your system.
aarch64:
rsync-3.1.2-11.amzn2.0.8.aarch64
rsync-debuginfo-3.1.2-11.amzn2.0.8.aarch64
i686:
rsync-3.1.2-11.amzn2.0.8.i686
rsync-debuginfo-3.1.2-11.amzn2.0.8.i686
src:
rsync-3.1.2-11.amzn2.0.8.src
x86_64:
rsync-3.1.2-11.amzn2.0.8.x86_64
rsync-debuginfo-3.1.2-11.amzn2.0.8.x86_64