Authorization Bypass in ON24 Q&A chat

published 2026-03-30 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-17084

cvss: 8.7; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits: 0; none known

A vulnerability of authorization bypass through user-controlled key in the 'console-survey/api/v1/answer/{EVENTID}/{TIMESTAMP}/' endpoint. Exploiting this vulnerability would allow an unauthenticated attacker to enumerate event IDs and obtain the complete Q&A history. This publicly exposed data may include IDs, private URLs, private messages, internal references, or other sensitive information that should only be exposed to authenticated users. In addition, the leaked content could be exploited to facilitate other malicious activities, such as reconnaissance for lateral movement, exploitation of related systems, or unauthorised access to internal applications referenced in the content of chat messages.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 7 mo ago (2026-03-30)

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/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

Affected products

ON24 ON24 Q&A chat

Classification

Weakness

CWE-639 Authorization Bypass Through User-Controlled Key

References

incibe.es /en/incibe-cert/notices/aviso/authorization-bypass-on24-qa-chat

Sources

CVE List CVE-2026-3321
NVD CVE-2026-3321

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Summary