CVE-2026-53792 rsync < 3.5.0 Out-of-Bounds Read via Zero-Length Checksum Block
A malicious receiver can trigger an out-of-bounds read on the rsync sender by sending a zero-length checksum block, potentially leaking memory or causing a crash.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-53792?
CVE-2026-53792 is a high-severity memory corruption vulnerability in RsyncProject rsync, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
rsync before 3.5.0 contains an out-of-bounds read vulnerability in the sender-side block matching logic that allows a malicious receiver to trigger memory access before the start of an allocated buffer by sending a crafted checksum block with a length of zero. Attackers can send a specially crafted checksum set containing a zero-length block to cause a negative offset calculation during delta computation, resulting in an out-of-bounds read of file data buffer memory on the sender side.
Which versions are affected by CVE-2026-53792?
How do I fix CVE-2026-53792?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-53792 being exploited?
There is no known exploitation of CVE-2026-53792 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-53792, AZL-95786, BELL-CVE-2026-53792, DEBIAN-CVE-2026-53792, ECHO-bf04-0160-41b5, GHSA-cg57-rp9g-56hw and 1 more.