CVE-2021-22893 — Ivanti Pulse Connect Secure Use-After-Free Vulnerability
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Confirmed exploitation (CISA KEV)+35
- Used in ransomware campaigns (CISA)+10
- Public exploit/PoC (github)+6
- EPSS 47.2% (30-day exploitation probability)+15
- Technical severity (critical)+10
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
CISA required action CISA
Apply updates per vendor instructions.
US federal deadline: May 3, 2022 — passed 1626 day(s) ago
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Ivanti Connect Secure).
- Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- EPSS ahead of 99% of scored CVEs: prioritize it in the patch queue.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Ivanti | Connect Secure |
version 9.1-r6version 9.1-r11.3version 9.1-r2version 9.1-r3version 9.1-r4version 9.1-r4.1version 9.1-r4.2version 9.1-r4.3 and 28 moreversion 9.1-r5version 9.1-r11.1version 9.1-r7version 9.1-r8version 9.1-r8.1version 9.1-r8.2version 9.1-r8.4version 9.1-r9version 9.1-r9.1version 9.1-r9.2version 9.0-r4version 9.0-r1version 9.0-r2version 9.0-r2.1version 9.0-r3version 9.0-r3.1version 9.0-r3.2version 9.0-r3.3version 9.0-r3.5version 9.0version 9.0-r4.1version 9.0-r5.0version 9.0-r6.0version 9.1version 9.1-r1version 9.1-r10.0version 9.1-r10.2version 9.1-r11.0 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 10.0 | CVSS 3.1 | Critical | 3.9 | 6.0 | nvd@nist.gov via NIST National Vulnerability Database |
| 10.0 | CVSS 3.1 | Critical | 3.9 | 6.0 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 10.0 | CVSS 3.1 | Critical | — | — | GitHub, Inc. via GitHub Security Advisories |
| 10.0 | CVSS 3.1 | Critical | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
| 7.5 | CVSS 2.0 | High | 10.0 | 6.4 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CISA KEV details CISA
CISA lists a CVE once it has evidence of exploitation against real targets.
CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.
Public exploits, PoCs and detection templates
Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.
- DO NOT RUN THIS. ★ 47 Apr 21, 2021
- Proof On Concept — Pulse Secure CVE-2021-22893 ★ 7 Oct 3, 2021
- Pulse Connect Secure RCE Vulnerability (CVE-2021-22893) ★ 0 Apr 21, 2021
Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 47.17%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
- Hunt retroactively in logs from before Nov 3, 2021 (KEV listing): exploitation may have started earlier.
Timeline
What happened to this CVE, newest first.
- 2026
- SSVC assessment updated
- Record published
- Affected products added · ivanti/connect secure
- CVSS changed · 10.0
- Source status changed · → Analyzed
- Added to CISA KEV (detected)
- Record created in this database
- 2021
- Added to CISA KEV catalog
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 13, 2026 – Oct 13, 2026
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
10 on the record
- blog.pulsesecure.net/pulse-connect-secure-security-update/
- kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784/
- www.cisa.gov/known-exploited-vulnerabilities-catalog
- www.kb.cert.org/vuls/id/213092
- kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44784
- www.fireeye.com/blog/threat-research/2021/04/suspected-apt-actors-leverage-bypass-tec
- github.com/advisories/GHSA-hcxw-prp6-q3jq
- nvd.nist.gov/vuln/detail/CVE-2021-22893
- kb.cert.org/vuls/id/213092
- blog.pulsesecure.net/pulse-connect-secure-security-update
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-111357 Ivanti Connect Secure 22.8R2.4 mishandles the manner in which the dsinvoked broker… 1h
- High CVE-2026-104935 Ivanti Connect Secure Authentication Bypass by Spoofing Vulnerability KEV 2d
- Critical CVE-2025-22457 Ivanti Connect Secure, Policy Secure, and ZTA Gateways Stack-Based Buffer Overflow Vulnerability KEV Apr 3, 2025
- Critical CVE-2025-0282 Ivanti Connect Secure, Policy Secure, and ZTA Gateways Stack-Based Buffer Overflow Vulnerability KEV Jan 8, 2025
- High CVE-2024-21893 Ivanti Connect Secure, Policy Secure, and Neurons Server-Side Request Forgery (SSRF) Vulnerability KEV Jan 31, 2024
- Critical CVE-2024-21887 Ivanti Connect Secure and Policy Secure Command Injection Vulnerability KEV Jan 12, 2024
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2021-22893 is "Ivanti Pulse Connect Secure Use-After-Free Vulnerability", rated Critical. It affects Connect Secure (Ivanti); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 10.0 describes technical severity. EPSS 47.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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