CVE-2021-31583

Exp

Sipwise C5 NGCP WWW Admin version 3.6.7 up to and including platform version NGCP CE 3.0 has multiple authenticated stored and reflected XSS vulnerabilities when input passed via several parameters to several scripts is not properly sanitized before being returned to the user: Stored XSS in callforward/time/set/save (POST tsetname); Reflected XSS in addressbook (GET filter); Stored XSS in addressbook/save (POST firstname, lastname, company); and Reflected XSS in statistics/versions (GET lang).

Published: 2021-04-23 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-31583 is rated Exploit Available (58.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.12%). Core evidence: 4 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-31583

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-31583

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.89% 1.12% +0.23%
2 2025-11-21 0.96% 0.89% -0.07%
3 2025-11-18 0.96%

Full EPSS history (18 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-31583

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.3 2.7 [email protected]
3.5 2.0 LOW
AV:N/AC:M/Au:S/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
6.8 2.9 [email protected]

Weakness enumeration for CVE-2021-31583

Affected software / configurations for CVE-2021-31583

Vendor Product Version Raw CPE
sipwise next_generation_communication_platform 3.6.7 cpe:2.3:a:sipwise:next_generation_communication_platform:3.6.7:*:*:*:ce:*:*:*

References for CVE-2021-31583

cvelogic Threat Intelligence