CVE-2016-20033

Name: CVE-2016-20033
Creator: NVD / NIST
Published: 2026-03-16T14:17:50.297+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.5/10EPSS 0.21%

Last modified Jun 17, 2026

CVE-2016-20033 is a high-severity vulnerability rated 8.5/10 on the CVSS scale. 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.. EPSS estimates a 0.21% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS 4.0

8.5/10

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

EPSS Probability

0.21%

11.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-639

Affected Software

Vendor	Product	Versions
Wowza	Streaming Engine	4.5.0

References

http://www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5339.phpExploit, Third Party Advisory
https://www.exploit-db.com/exploits/40132Exploit, Third Party Advisory, VDB Entry
https://www.vulncheck.com/advisories/wowza-streaming-engine-local-privilege-escalation-via-nssm-x64-exeThird Party Advisory

Timeline

Published: Mar 16, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2016-20033?

How severe is CVE-2016-20033?

CVE-2016-20033 has a CVSS score of 8.5/10 (HIGH severity). The EPSS model estimates a 0.21% probability of exploitation in the next 30 days.

How do I fix CVE-2016-20033?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2016-20033?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST