CVE-2016-8581

Exp

A persistent XSS vulnerability exists in the User-Agent header of the login process of AlienVault OSSIM and USM before 5.3.2 that allows an attacker to steal session IDs of logged in users when the current sessions are viewed by an administrator.

Published: 2016-10-28 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-8581 is rated High Exploit Risk (75.7/100): CVSS Medium severity, with high exploitation likelihood (EPSS 68.15%, 99th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.79% over the last day, indicating growing attacker interest. 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-2016-8581

EDB-ID Source Kind Published Link
40683 exploit_db edb 2016-11-02 Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2016-8581

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 2025-08-23 66.36% 68.15% +1.79%
2 2025-03-30 64.08% 66.36% +2.29%
3 2025-03-29 — 64.08% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-8581

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/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:N)
No account or special rights needed—anonymous or random user is enough.
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.
 2.8 2.7 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/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:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2016-8581

Affected software / configurations for CVE-2016-8581

Vendor Product Version Raw CPE
alienvault open_source_security_information_and_event_management <= 5.3.1 cpe:2.3:a:alienvault:open_source_security_information_and_event_management:*:*:*:*:*:*:*:*
alienvault unified_security_management <= 5.3.1 cpe:2.3:a:alienvault:unified_security_management:*:*:*:*:*:*:*:*

References for CVE-2016-8581

cvelogic Threat Intelligence