CVE-2026-70453

rsync < 3.5.0 Algorithmic Complexity DoS via hash_search()

HIGH
7.5
CVSS Score
Published: August 13, 2026 at 02:46 PM UTC
Updated: October 24, 2026 at 04:10 PM UTC
2 products affected across 2 vendorsRsyncRsync

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Severity
HIGH7.5
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 3.4.4
0 ≤ v ≤ 3.4.40
Vendor states this is fixed in 3.5.0 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHVulnCheck
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-407

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