CVE-2021-22893
CVE-2021-22893 is a security flaw in Ivanti Pulse Connect Secure, a VPN companies use to let staff in from outside. Attackers can run their own code on Ivanti Pulse Connect Secure from anywhere, without logging in. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 3 Nov 2021, and says ransomware gangs have used it.[1]
Ivanti Pulse Connect Secure is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Ivanti has published a fix or advice.
Description
CISA calls it an use-after-free in Ivanti Pulse Connect Secure. In its words: “Ivanti Pulse Connect Secure contains a use-after-free vulnerability that allow a remote, unauthenticated attacker to execute code via license services.”[1]
The CVE record adds: “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.”[2]
The underlying weakness is improper authentication (CWE-287), in MITRE’s list of common software weaknesses.
It scores 10.0 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Ivanti’s advisory has them[3]. CISA names the product as Ivanti Pulse Connect Secure.
Most families won’t have Ivanti Pulse Connect Secure; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 3 Nov 2021, 194 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 3 May 2022 to fix it.[1] CISA says ransomware gangs have used it.
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 47%. That’s in the top 2% of the flaws it scores.[4]
CISA assesses it as automatable: attackers can run it against many targets at once.
CISA doesn’t say who was attacked, or how.
Fix
Ivanti has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.Ivanti Pulse Connect Secure is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 3 May 2022 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 10.0.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks, noting that ransomware gangs have used it.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 47%.[4] |
See also
Other Ivanti Pulse Connect Secure flaws
- CVE-2021-22900: unrestricted file upload ·
- CVE-2021-22899: command injection ·
- CVE-2021-22894: collaboration suite buffer overflow ·
- CVE-2020-8260: code execution ·
- CVE-2020-8243: code execution ·
- CVE-2019-11510: arbitrary file read ·
Other Ivanti flaws
- CVE-2026-118527, Ivanti Connect Secure: generation of predictable numbers or identifiers ·
- CVE-2026-111357, Ivanti Connect Secure: missing authentication for critical function ·
- CVE-2026-104935, Ivanti Connect Secure: authentication bypass by spoofing ·
- CVE-2026-10520, Ivanti Sentry: OS command injection ·
- CVE-2026-6973, Ivanti Endpoint Manager Mobile (EPMM): improper input validation ·
Other improper authentication flaws
- CVE-2026-105133, AhsayCBS: improper authentication ·
- CVE-2026-42018, JFrog Artifactory: improper authentication ·
- CVE-2026-82329, JFrog Artifactory: improper authentication ·
- CVE-2026-59822, BerriAI LiteLLM: improper authentication ·
- CVE-2023-49105, ownCloud: improper authentication ·
Added the same day
- CVE-2021-42258, BQE BillQuick Web Suite: SQL injection ·
- CVE-2021-42013, Apache HTTP Server: path traversal ·
- CVE-2021-41773, Apache HTTP Server: path traversal ·
- CVE-2021-40539, Zoho ManageEngine: aDSelfService plus authentication bypass ·
- CVE-2021-40444, Microsoft MSHTML: remote code execution ·
Every Ivanti flaw on CISA’s list · Everything added in November 2021
References
- ^ Cybersecurity and Infrastructure Security Agency. “Ivanti Pulse Connect Secure Use-After-Free Vulnerability”. Known Exploited Vulnerabilities Catalog, added 3 Nov 2021.
- ^ National Institute of Standards and Technology. “CVE-2021-22893 Detail”. National Vulnerability Database, published 23 Apr 2021.
- ^ Ivanti. Advisories and fixes: blog.pulsesecure.net.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.472, percentile 98.8, 31 Oct 2026.
- CVE Program. “CVE-2021-22893”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.