CVE-2016-20033 json
Wowza Streaming Engine 4.5.0 Local Privilege Escalation via nssm_x64.exe
published 2026-03-15 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2016-10821
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 12%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 7 mo ago
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- exploit-db.com https://www.exploit-db.com/exploits/40132 referenced PoC, tagged "exploit" by a source, unverified
- zeroscience.mk http://www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5339.php referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Wowza Media Systems, LLC. Wowza Streaming Engine
Classification
- Weakness
-
- CWE-639 Authorization Bypass Through User-Controlled Key
References
-
exploit-db.com
/exploits/40132
exploit, third-party-advisory, vdb-entry
-
zeroscience.mk
/en/vulnerabilities/ZSL-2016-5339.php
vendor-advisory, exploit, third-party-advisory
-
vulncheck.com
/advisories/wowza-streaming-engine-local-privilege-escalation-via-nssm-x64-exe
third-party-advisory
Sources
- CVE List CVE-2016-20033
- NVD CVE-2016-20033
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.