# CVE-2021-22894 — Pulse Connect Secure

**CISA KEV**

> As of 2025-10-21, CVE-2021-22894 is a HIGH-severity vulnerability in Pulse Connect Secure, CVSS v3.1 8.8, EPSS 41.2% (98.5th percentile). It is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), with a US federal remediation deadline of 2022-05-03. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2021-22894, most recently “Sen. Wyden Urges Binding Federal Mandate to Purge Internet-Facing Legacy VPNs for Zero-Trust Remote Access”.

**Last updated:** 2025-10-21

## What is CVE-2021-22894?

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 record classifies CVE-2021-22894 under weakness class [CWE-94](https://intel.threadlinqs.com/cwe/CWE-94). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 1957 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.8 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **EPSS (FIRST):** 41.2% probability of exploitation in the next 30 days, higher than 98.5% of all scored CVEs
- **CISA KEV:** Listed since 2021-11-03, federal remediation deadline 2022-05-03
- **Threadlinqs priority:** 9/10 — CISA KEV-listed, which Threadlinqs floors at 9
- **Published:** 2021-05-27, last modified 2025-10-21

## Is CVE-2021-22894 being exploited?

CISA added CVE-2021-22894 to the Known Exploited Vulnerabilities catalog on 2021-11-03, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2022-05-03 under BOD 22-01. Weaponised exploit code for CVE-2021-22894 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 43 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2021/CVE-2021-22894.md) (trickest)

## Affected products and versions

- **(vendor unspecified)**: Pulse Connect Secure

## How to fix CVE-2021-22894

Vendor advisory: [https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/?kA23Z000000boUWSAY](https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/?kA23Z000000boUWSAY). Because CVE-2021-22894 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2022-05-03. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2021-22894

1 tracked threat in the Threadlinqs corpus references CVE-2021-22894, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Sen. Wyden Urges Binding Federal Mandate to Purge Internet-Facing Legacy VPNs for Zero-Trust Remote Access](https://intel.threadlinqs.com/threat/TL-2026-1774) — MEDIUM · 2026-07-27

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-07-30. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [kb.pulsesecure.net](https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/?kA23Z000000boUWSAY)

Canonical: https://intel.threadlinqs.com/cve/CVE-2021-22894
Full detection coverage and IOCs for threats exploiting CVE-2021-22894 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp