CVE-2026-70456 rsync 3.0.1 < 3.5.0 Heap Out-of-Bounds Write via read_args()
A malicious sender can trigger a heap out-of-bounds write in rsync via crafted arguments, potentially leading to code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-70456?
CVE-2026-70456 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, with no action from the victim.
Official description
rsync 3.0.1 before 3.5.0 contains an out-of-bounds write vulnerability in the read_args() function that allows a malicious sender to corrupt adjacent heap memory by sending a crafted argument list. When the argument count causes the argv allocation to be exactly full, the trailing NULL terminator is written one slot beyond the allocation boundary, corrupting adjacent heap memory.
Weakness: CWE-787
Which versions are affected by CVE-2026-70456?
How do I fix CVE-2026-70456?
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-2026-70456 being exploited?
There is no known exploitation of CVE-2026-70456 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-70456, AZL-95843, BELL-CVE-2026-70456, CLSA-2026-1789569255, CLSA-2026-1789569581, CLSA-2026-1789579460 and 9 more.