CVE-2026-70453

rsync before 3.5.0 contains an algorithmic complexity vulnerability in the hash_search() function that allows a remote attacker to cause a denial of service by delivering a carefully constructed file list. A sender can exploit the quadratic-time worst-case behavior in hash lookups to exhaust receiver CPU resources with a modest number of crafted entries, causing a sustained denial of service.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
https://github.com/RsyncProject/rsync/security/advisories/GHSA-8x5r-mjx8-83hv
https://www.vulncheck.com/advisories/rsync-algorithmic-complexity-dos-via-hash-search

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 15:19

Updated : 2026-09-08 20:28

NVD link : CVE-2026-70453

Mitre link : CVE-2026-70453

CVE.ORG link : CVE-2026-70453

JSON object : View

Products Affected

No product.

CWE

CWE-407

Inefficient Algorithmic Complexity

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