CVE-2026-70455: rsync 3.4.2 before 3.5.0 contains a denial of service vulnerability that allows a remote sender to exhaust system…
CVE-2026-70455 · Severity: high · CVSS 7.5 · Published 2026-08-13
rsync 3.4.2 before 3.5.0 contains a denial of service vulnerability that allows a remote sender to exhaust system resources by specifying the --zt short alias for --compress-threads, which bypasses the refuse options directive's string matching on long option names. Attackers can specify --zt=N with a large value to spawn an unbounded number of Zstandard worker threads on the receiver, exhausting available thread and memory resources.
No. Junglewise Threat Intelligence has no report of CVE-2026-70455 being exploited in the wild.
How severe is CVE-2026-70455?
High severity, with a CVSS score of 7.5, published 13 August 2026.
Which products and versions are affected?
Samba Rsync. The advisory does not name versions.
Is there a fix for CVE-2026-70455?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-70455?
Check whether you run Samba Rsync. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.