NVD security advisoryHigh
High advisory for rsync
CVE-2026-119741 · Reported 3 Nov 2026
Full advisory details, affected packages, severity context, and original source.
Affected technology
rsyncAffected product
Advisory overview
rsync through 3.5.1 contains a denial of service vulnerability in the delta-transfer sender's hash_search() in match.c that allows malicious receivers to trigger unbounded strong-checksum work at consecutive offsets. Unauthenticated attackers pulling from a public daemon module can supply weak checksums colliding with consecutive rolling windows plus non-matching strong checksums, exhausting sender CPU across concurrent connections.
Related references
- https://github.com/RsyncProject/rsync
- https://github.com/RsyncProject/rsync/blob/a7404a9a633cff28ee1602f328b9c3fa69cdbd04/testsuite/hashsearch-collision-skip_test.py
- https://github.com/RsyncProject/rsync/commit/a7404a9a633cff28ee1602f328b9c3fa69cdbd04
- https://github.com/RsyncProject/rsync/pull/1132
- https://www.vulncheck.com/advisories/rsync-through-3.5.1-denial-of-service-via-hash-search-checksum-collisions