Out-of-Bounds Write Vulnerability in Rsync by Rsync Project
CVE-2026-70458

8.8HIGH

Key Information:

Vendor

Rsyncproject

Status
Rsync
Vendor
CVE Published:
13 August 2026

What is CVE-2026-70458?

An out-of-bounds write vulnerability exists in Rsync versions prior to 3.5.0, allowing attackers to corrupt memory. This issue arises from the HLINK_BUMP processing on file entries marked with the FLAG_HLINKED flag, specifically when the hard-link preservation option is turned off. The vulnerability stems from the absence of the F_SUM field in the file_struct layout, permitting exploiters to overwrite memory boundaries and potentially compromise adjacent heap or stack data.

Affected Version(s)

rsync 3.0.0 <= 3.4.4

rsync 3.5.0

References

https://github.com/RsyncProject/rsync/security/advisories...
vendor-advisory
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
release-notes
https://www.vulncheck.com/advisories/rsync-out-of-bounds-...
third-party-advisory

CVSS V4

Score:
8.8
Severity:
HIGH
Confidentiality:
None
Integrity:
Low
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

gregkh
.