CVE-2026-70461

A flaw was found in rsync. Remote unauthenticated attackers can exploit a heap out-of-bounds write vulnerability by supplying a crafted files-from entry. This entry, containing both an interior and trailing backslash, causes the add_implied_include() function to under-count the trailing backslash when sizing the destination buffer. This can lead to information disclosure or denial of service.

This is an Important vulnerability in rsync that allows remote unauthenticated attackers to achieve information disclosure and denial of service. The flaw occurs in the rsync daemon when processing a specially crafted files-from entry, leading to a heap out-of-bounds write. This can be exploited against read-only rsync daemon modules, making it a significant risk for publicly exposed rsync services.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Restrict access to the rsync daemon (TCP 873) to trusted hosts with firewall rules. If the daemon is unused, disable and stop rsyncd.service.