CVE-2026-70455
Description
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Debian Affected 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Affected | — |
| sid | Affected | — |
| forky | Affected | — |
| bullseye | Affected | — |
| bookworm | Affected | — |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
References
- https://www.suse.com/security/cve/CVE-2026-70455.html
- https://security-tracker.debian.org/tracker/CVE-2026-70455
- https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
- https://github.com/RsyncProject/rsync/security/advisories/GHSA-rjvj-qgqg-cvx9
- https://www.vulncheck.com/advisories/rsync-dos-via-zt-zstandard-compression-thread-exhaustion
CWEs
CWE-770
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.