CVE-2016-6603
ZOHO WebNMS Framework 5.2 and 5.2 SP1 allows remote attackers to bypass authentication and impersonate arbitrary users via the UserName HTTP header.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 86.9%, higher than 100% of all known CVEs. Patch or mitigate before the next change window.
Description
ZOHO WebNMS Framework 5.2 and 5.2 SP1 allows remote attackers to bypass authentication and impersonate arbitrary users via the UserName HTTP header.
- CVSS 3.0
- 9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 86.93% probability · 100th percentile
- Public exploits
- 1 in Exploit-DB · first 10 August 2016
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- zohocorp/webnms framework
- Source
- cve@mitre.org
EPSS moved from 48.8% on 21 September 2026 to 86.9% on 4 November 2026, peaking at 87.0% on 22 September 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
Public exploits (1)
Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.
References
- http://packetstormsecurity.com/files/138244/WebNMS-Framework-5.2-SP1-Traversal-Weak-Obfuscation-User-Impersonation.htmlExploit, Third Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2016/Aug/54Exploit, Mailing List, Third Party Advisory
- http://www.securityfocus.com/archive/1/539159/100/0/threaded
- http://www.securityfocus.com/bid/92402Third Party Advisory, VDB Entry
- https://blogs.securiteam.com/index.php/archives/2712Exploit, Technical Description, Third Party Advisory
- https://forums.webnms.com/topic/recent-vulnerabilities-in-webnms-and-how-to-protect-the-server-against-them
- https://github.com/pedrib/PoC/blob/master/advisories/webnms-5.2-sp1-pwn.txtExploit, Third Party Advisory
- https://www.exploit-db.com/exploits/40229/Exploit, Third Party Advisory, VDB Entry
- http://packetstormsecurity.com/files/138244/WebNMS-Framework-5.2-SP1-Traversal-Weak-Obfuscation-User-Impersonation.htmlExploit, Third Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2016/Aug/54Exploit, Mailing List, Third Party Advisory
- http://www.securityfocus.com/archive/1/539159/100/0/threaded
- http://www.securityfocus.com/bid/92402Third Party Advisory, VDB Entry
- https://blogs.securiteam.com/index.php/archives/2712Exploit, Technical Description, Third Party Advisory
- https://forums.webnms.com/topic/recent-vulnerabilities-in-webnms-and-how-to-protect-the-server-against-them
- https://github.com/pedrib/PoC/blob/master/advisories/webnms-5.2-sp1-pwn.txtExploit, Third Party Advisory
- https://www.exploit-db.com/exploits/40229/Exploit, Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.