CVE-2019-15987 | Cisco WebEx Centers Username Enumeration Information Disclosure Vulnerability

A vulnerability in web interface of the Cisco Webex Event Center, Cisco Webex Meeting Center, Cisco Webex Support Center, and Cisco Webex Training Center could allow an unauthenticated, remote attacker to guess account usernames. The vulnerability is due to missing CAPTCHA protection in certain URLs. An attacker could exploit this vulnerability by sending a crafted request to the web interface. A successful exploit could allow the attacker to know if a given username is valid and find the real name of the user.

Published: 2019-11-25 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2019-15987 is rated Moderate Risk (47.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.58%). Mandatory action: Review affected assets and schedule remediation.

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

Exploit prediction scoring system (EPSS) score for CVE-2019-15987

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 0.90% 1.58% +0.68%
2 2025-11-21 0.42% 0.90% +0.48%
3 2025-11-18 0.42%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-15987

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]
5.3 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2019-15987

Affected software / configurations for CVE-2019-15987

Vendor Product Version Raw CPE
cisco webex_meetings_online 11.0.0 cpe:2.3:a:cisco:webex_meetings_online:11.0.0:*:*:*:*:*:*:*
cisco webex_meetings_server 4.0 cpe:2.3:a:cisco:webex_meetings_server:4.0:*:*:*:*:*:*:*
cisco webex_event_center cpe:2.3:a:cisco:webex_event_center:-:*:*:*:*:*:*:*
cisco webex_meeting_center cpe:2.3:a:cisco:webex_meeting_center:-:*:*:*:*:*:*:*
cisco webex_support_center cpe:2.3:a:cisco:webex_support_center:-:*:*:*:*:*:*:*
cisco webex_training_center cpe:2.3:a:cisco:webex_training_center:-:*:*:*:*:*:*:*

References for CVE-2019-15987

cvelogic Threat Intelligence