CVE-2021-22893

CVE-2021-22893 is a critical-severity (CVSS 10.0) vulnerability in Ivanti Pulse Connect Secure. CISA added it to the Known Exploited Vulnerabilities catalog on November 3, 2021, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by May 3, 2022. CISA also lists it as known to be used in ransomware campaigns, so it should be prioritised accordingly. Ivanti has 38 vulnerabilities in the KEV catalog, 12 of them linked to ransomware.

Pulse Connect Secure 9.0R3/9.1R1 and higher is vulnerable to an authentication bypass vulnerability exposed by the Windows File Share Browser and Pulse Secure Collaboration features of Pulse Connect Secure that can allow an unauthenticated user to perform remote arbitrary code execution on the Pulse Connect Secure gateway. This vulnerability has been exploited in the wild.

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

• https://blog.pulsesecure.net/pulse-connect-secure-security-update/
• https://kb.cert.org/vuls/id/213092
• https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/
• https://www.fireeye.com/blog/threat-research/2021/04/suspected-apt-actors-leverage-bypass-techniques-pulse-secure-zero-day.html
• https://blog.pulsesecure.net/pulse-connect-secure-security-update/
• https://kb.cert.org/vuls/id/213092
• https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/
• https://www.fireeye.com/blog/threat-research/2021/04/suspected-apt-actors-leverage-bypass-techniques-pulse-secure-zero-day.html