CVEs / CVE-2021-22894

CVE-2021-22894: Ivanti Pulse Connect Secure Collaboration Suite Buffer Overflow Vulnerability

Known exploited in the CISA KEV catalog since 3 Nov 2021
high 8.8 CVSS 3.1 (NVD)
EPSS 41.2% chance of exploitation in the next 30 days, higher than 98% of CVEs (30 Oct 2026)
Last changed at its sources 17 Jun 2026

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Summary

Ivanti Pulse Connect Secure Collaboration Suite contains a buffer overflow vulnerabilities that allows a remote authenticated users to execute code as the root user via maliciously crafted meeting room.
CISA, Known Exploited Vulnerabilities catalog

Description

A buffer overflow vulnerability exists in Pulse Connect Secure before 9.1R11.4 allows a remote authenticated attacker to execute arbitrary code as the root user via maliciously crafted meeting room.
The CVE record, via NVD · published 27 May 2021 · NVD status: Analyzed

Affected and fixed versions

As stated by the CVE record (from the CNA)
Product	Affected	Fixed in
n/a Pulse Connect Secure	Fixed version 9.1R11.4	—

Exploitation

In CISA KEV since	3 Nov 2021
Due date for US federal agencies	3 May 2022
Used in ransomware campaigns	Unknown
Required action	Apply updates per vendor instructions.

Severity

CVSS 3.1	8.8 high `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Scored by NVD
Weakness	CWE-94, CWE-119

References

CVE-2021-22894 on NVD
CVE-2021-22894 in the CISA KEV catalog
https://www.cisa.gov/news-events/directives/ed-21-03-mitigate-pulse-connect-secure-product-vulnerabilities (cited by CISA)
https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/?kA23Z000000boUWSAY Broken Link, Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22894 US Government Resource

Sources

Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.

This product uses data from the NVD API but is not endorsed or certified by the NVD.