CVE-2026-43617: medium-severity vulnerability in RsyncProject rsync
Rsync < 3.4.3 Authorization Bypass via Hostname Resolution
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.3%
Rsync version 3.4.2 and prior contain an authorization bypass vulnerability in the rsync daemon's hostname-based access control list enforcement when configured with chroot. Attackers can bypass hostname-based deny rules by controlling the PTR record for their source IP address, allowing connections from hostnames that administrators intended to deny when reverse DNS resolution fails and defaults to UNKNOWN.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Affected products
RsyncProject · rsyncRelated CVEs — RsyncProject rsync
In the same product, most dangerous first.
CVE-2026-43618MEDIUMRsync < 3.4.3 Integer Overflow Information DisclosureEPSS 0.8%CVE-2026-70459MEDIUMrsync 3.0.0 < 3.5.0 Daemon Crash via Malformed File List EntryEPSS 0.7%CVE-2026-70464HIGHrsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake StallEPSS 0.6%CVE-2026-53790CRITICALrsync < 3.5.0 Command Injection via Multiple Code PathsEPSS 0.6%CVE-2026-119741HIGHrsync < 3.5.2 Denial of Service via hash_search() Checksum CollisionsEPSS 0.6%CVE-2026-70453HIGHrsync < 3.5.0 Algorithmic Complexity DoS via hash_search()EPSS 0.6%