CVE-2026-70456: rsync 3.0.1 < 3.5.0 Heap Out-of-Bounds Write via read_args()
CSIRTS triage
- What
- A heap out-of-bounds write in read_args() allows remote code execution via crafted command-line arguments.
- Who is affected
- rsync versions 3.0.1 through 3.4.x processing untrusted file list or argument data.
- Urgency
- High severity; remote code execution vulnerability with CVSS 8.2 that may be exploitable.
- Action
- Upgrade rsync to version 3.5.0 or later immediately.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-70456
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-704560.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-70456 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
Recent advisories for rsync
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- high[NEW] [high] Rsync: Multiple vulnerabilitiescert-bund · 2026-08-21
- high[UPDATE] [high] Rsync: Multiple vulnerabilitiescert-bund · 2026-08-19
- medium[UPDATE] [medium] Rsync: Vulnerability allows bypassing security measurescert-bund · 2026-08-18
- highCVE-2026-70464: rsync daemon 2.0.0 before 3.5.0 contains a denial of service vulnerability that allows unauthe…nvd · 2026-08-13
- highCVE-2026-70463: rsync 3.1.0 before 3.5.0 contains an authorization bypass in auth users directive parsing. The…nvd · 2026-08-13
- mediumCVE-2026-70462: rsync 3.1.0 before 3.5.0 contains a signed integer overflow vulnerability in the I/O timeout i…nvd · 2026-08-13
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