# CVE-2026-119741: rsync denial of service in hash_search()

Source: https://junglewise.ai/threats/cve-2026-119741-rsync-through-3-5-1-contains-a-denial-of-service-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-03. Updated: 2026-11-03  
License: CC BY 4.0 with a link back

CVE-2026-119741 · Severity: high · CVSS 7.5 · Published 2026-11-03

rsync is a file synchronization utility used for backups and incremental transfers. An attacker pulling files from a public rsync server can craft malicious checksums that force the sender to perform excessive CPU-intensive hash computations, causing a denial of service that could make the server unresponsive to legitimate users.

Technologies: [RsyncProject Rsync](https://junglewise.ai/threats/technologies/rsync). Vendors: [RsyncProject](https://junglewise.ai/threats/vendors/rsyncproject).

## Quick answers

**Is CVE-2026-119741 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-119741 being exploited in the wild.

**How severe is CVE-2026-119741?** High severity, with a CVSS score of 7.5, published 3 November 2026.

**Which products and versions are affected?** RsyncProject Rsync through 3.5.1.

**Is there a fix for CVE-2026-119741?** 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.

**How is CVE-2026-119741 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-119741?** Check whether you run RsyncProject Rsync at an affected version. 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.

## Technical details

The vulnerability exists in the delta-transfer sender's hash_search() function in match.c. An unauthenticated attacker can supply weak checksums that collide with consecutive rolling windows combined with non-matching strong checksums, triggering unbounded strong-checksum computation work. This can be exploited across multiple concurrent connections to exhaust sender CPU resources.

## Affected products

- RsyncProject rsync through 3.5.1

## Timeline

- 2026-11-03: disclosed

## References

- [https://github.com/RsyncProject/rsync](https://github.com/RsyncProject/rsync)
- [https://github.com/RsyncProject/rsync/blob/a7404a9a633cff28ee1602f328b9c3fa69cdbd04/testsuite/hashsearch-collision-skip_test.py](https://github.com/RsyncProject/rsync/blob/a7404a9a633cff28ee1602f328b9c3fa69cdbd04/testsuite/hashsearch-collision-skip_test.py)

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- [Rsync out-of-bounds read in recv_files](https://junglewise.ai/threats/cve-2026-44510-rsync-out-of-bounds-read-in-recv-files)
- [RsyncProject rsync symlink race in path-based syscalls](https://junglewise.ai/threats/cve-2026-44509-rsyncproject-rsync-symlink-race-in-path-based-syscalls)
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- [Rsync hostname ACL bypass in chroot daemon mode](https://junglewise.ai/threats/cve-2026-44507-rsync-hostname-acl-bypass-in-chroot-daemon-mode)
- [Rsync TOCTOU race condition in daemon file handling](https://junglewise.ai/threats/cve-2026-29518-rsync-toctou-race-condition-in-daemon-file-handling)