CVE-2023-39296
Published: April 11, 2026
Official Description
A prototype pollution vulnerability has been reported to affect several QNAP operating system versions. If exploited, the vulnerability could allow users to override existing attributes with ones that have incompatible type, which may lead to a crash via a network.
We have already fixed the vulnerability in the following versions:
QTS 5.1.3.2578 build 20231110 and later
QuTS hero h5.1.3.2578 build 20231110 and later
Technical Analysis
CVE-2023-39296 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2023-39296 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Exploit & PoC Resources
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2023-39296 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1