How severe is CVE-2022-21826?

CVE-2022-21826 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2022-21826 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 45% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-21826?

CVE-2022-21826 primarily affects Ivanti Connect Secure. In total, 39 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-21826?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2022-21826 published?

CVE-2022-21826 was published on 2022-09-30 and last updated on 2026-06-17.

CVE-2022-21826

CVE-2022-21826 is a medium-severity vulnerability in Ivanti Connect Secure with a CVSS 3.x base score of 5.4. Its EPSS exploit-prediction score of 45% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-444.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 45% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Ivanti Connect Secure
Published: 2022-09-30
Last modified: 2026-06-17

Description

Pulse Secure version 9.115 and below may be susceptible to client-side http request smuggling, When the application receives a POST request, it ignores the request's Content-Length header and leaves the POST body on the TCP/TLS socket. This body ends up prefixing the next HTTP request sent down that connection, this means when someone loads website attacker may be able to make browser issue a POST to the application, enabling XSS.

Frequently asked questions

What is CVE-2022-21826?: Pulse Secure version 9.115 and below may be susceptible to client-side http request smuggling, When the application receives a POST request, it ignores the request's Content-Length header and leaves the POST body on the TCP/TLS socket. This body ends up prefixing the next HTTP request sent down that connection, this means when someone loads website attacker may be able to make browser issue a POST to the application, enabling XSS.
How severe is CVE-2022-21826?: CVE-2022-21826 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2022-21826 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 45% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-21826?: CVE-2022-21826 primarily affects Ivanti Connect Secure. In total, 39 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-21826?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-21826 published?: CVE-2022-21826 was published on 2022-09-30 and last updated on 2026-06-17.

References

https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/Client-Side-Desync-Attack/

Affected products (39)

cpe:2.3:a:ivanti:connect_secure:9.1:-:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r1:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r1.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r10.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r10.2:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r11.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r11.1:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r11.3:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r11.4:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r12:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r12.1:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r12.2:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r13:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r15:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r2:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r2.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r3:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r3.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r4:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r4.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r4.1:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r4.2:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r4.3:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r5:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r5.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r6:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r6.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r7:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r7.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r8:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r8.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r8.1:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r8.2:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r8.4:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r9:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r9.0:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r9.1:*:*:*:*:*:*
cpe:2.3:a:ivanti:connect_secure:9.1:r9.2:*:*:*:*:*:*
cpe:2.3:a:pulsesecure:pulse_connect_secure:*:*:*:*:*:*:*:*

More vulnerabilities in Ivanti Connect Secure

CVE-2021-22893 — Critical (CVSS 10.0): Pulse Connect Secure 9.0R3/9.1R1 and higher is vulnerable to an authentication bypass vulnerability exposed by the…
CVE-2019-11510 — Critical (CVSS 10.0): In Pulse Secure Pulse Connect Secure (PCS) 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4, an…
CVE-2016-4787 — Critical (CVSS 10.0): Pulse Connect Secure (PCS) 8.2 before 8.2r1, 8.1 before 8.1r2, 8.0 before 8.0r10, and 7.4 before 7.4r13.4 allow remote…
CVE-2025-22467 — Critical (CVSS 9.9): A stack-based buffer overflow in Ivanti Connect Secure before version 22.7R2.6 allows a remote authenticated attacker…
CVE-2024-21894 — Critical (CVSS 9.8): A heap overflow vulnerability in IPSec component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure allows…
CVE-2018-20813 — Critical (CVSS 9.8): An input validation issue has been found with login_meeting.cgi in Pulse Secure Pulse Connect Secure 8.3RX before 8.3R2.

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