Cisco Webex Software Application Authorization Bypass Vulnerability

published 2021-10-21 5y ago modified 2026-06-17 4mo ago also EUVD-2021-21393

cvss: 4.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits: 0; none known

A vulnerability in the application integration feature of Cisco Webex Software could allow an unauthenticated, remote attacker to authorize an external application to integrate with and access a user's account without that user's express consent. This vulnerability is due to improper validation of cross-site request forgery (CSRF) tokens. An attacker could exploit this vulnerability by convincing a targeted user who is currently authenticated to Cisco Webex Software to follow a link designed to pass malicious input to the Cisco Webex Software application authorization interface. A successful exploit could allow the attacker to cause Cisco Webex Software to authorize an application on the user's behalf without the express consent of the user, possibly allowing external applications to read data from that user's profile.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2y ago (2024-11-07)

Exploit prediction

0.47% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
NVD	3.1	7.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N
NVD	2.0	5.8	AV:N/AC:M/Au:N/C:P/I:P/A:N

Affected products

Cisco Cisco Webex Meetings

Classification

Weakness

CWE-352 Cross-Site Request Forgery

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-2FmKd7T
vendor-advisory

Sources

CVE List CVE-2021-34743
NVD CVE-2021-34743

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