Auth bypass in Wowza Streaming Engine
CVE-2016-20033
Wowza Streaming Engine 4.5.0 contains a local privilege escalation vulnerability that allows authenticated users to escalate privileges by replacing executable files due to improper file permissions granting full access to the Everyone group. Attackers can replace the nssm_x64.exe binary in the manager and engine service directories with malicious executables to execute code with LocalSystem privileges when services restart.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (9.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 9.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Wowza Streaming Engine — versions 4.5.0
- Wowza Media Systems, Llc. Streaming Engine — versions 4.5.0
Weakness classification (CWE)
References
- www.exploit-db.com/exploits/40132 (Exploit, VDB Entry, Third Party Advisory, exploit)
- www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5339.php (Exploit, vendor-advisory, Third Party Advisory)
- www.vulncheck.com/advisories/wowza-streaming-engine-local-privilege-escalation-… (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2016-20033?
- CVE-2016-20033 is a high-severity vulnerability in Wowza Streaming Engine, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 7.8/10. Published 2026-03-16.
- How severe is CVE-2016-20033?
- High severity. CVSS v3 base score is 7.8 out of 10.