CVE-2026-70455: high-severity vulnerability in RsyncProject rsync
rsync 3.4.2 < 3.5.0 DoS via --zt Zstandard Compression Thread Exhaustion
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.6%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
RsyncProject · rsyncRelated CVEs — RsyncProject rsync
In the same product, most dangerous first.
CVE-2026-43618MEDIUMRsync < 3.4.3 Integer Overflow Information DisclosureEPSS 0.8%CVE-2026-70459MEDIUMrsync 3.0.0 < 3.5.0 Daemon Crash via Malformed File List EntryEPSS 0.7%CVE-2026-70464HIGHrsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake StallEPSS 0.6%CVE-2026-53790CRITICALrsync < 3.5.0 Command Injection via Multiple Code PathsEPSS 0.6%CVE-2026-119741HIGHrsync < 3.5.2 Denial of Service via hash_search() Checksum CollisionsEPSS 0.6%CVE-2026-70453HIGHrsync < 3.5.0 Algorithmic Complexity DoS via hash_search()EPSS 0.6%