CVE-2026-70455

Summary

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.

Affected Software

VendorProductVersion RangeStatus
RsyncProjectrsync3.4.2 <= 3.4.4affected
RsyncProjectrsync3.5.0unaffected

Weaknesses

  • CWE-770: CWE-770 Allocation of Resources Without Limits or Throttling

References