Ivanti Connect Secure flaw massively exploited by attackers (CVE-2024-21893)

Ivanti Connect Secure (formerly Pulse Connect Secure) and Ivanti Policy Secure appliances contain a command injection flaw (CWE-77) in their web components, triggered when an authenticated administrator sends crafted requests to the appliance. The bug can be chained with the separate authentication bypass CVE-2023-46805, allowing an unauthenticated attacker to achieve the same result. Successful exploitation lets an attacker execute arbitrary commands and code on the appliance, providing a foothold into the networks behind the VPN or network access control gateway. Any organization running these appliances, typically enterprises and government agencies often deployed directly on the internet perimeter, is affected. Exploitation is confirmed in the wild: the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2024-01-10 with known ransomware use and EPSS assigns a 100% probability of exploitation within 30 days, although no public proof-of-concept is available.

Do: Apply Ivanti's mitigations or patched builds immediately per vendor instructions, addressing the chained authentication bypass CVE-2023-46805 at the same time, and discontinue or restrict use of any appliance for which mitigations are unavailable, especially if it is internet-facing. Because exploitation with ransomware use is known, assume compromise is possible: review appliance web logs for suspicious requests and run Ivanti's integrity-checking guidance to verify appliance images before and after remediation. Where feasible, restrict direct internet exposure of the appliance web interface and monitor for further vendor advisories.

A privilege escalation vulnerability in web component of Ivanti Connect Secure (9.x, 22.x) and Ivanti Policy Secure (9.x, 22.x) allows a user to elevate privileges to that of an administrator.

CVE-2024-21893 is a server-side request forgery (SSRF) vulnerability in the SAML component of Ivanti Connect Secure (formerly Pulse Connect Secure), Ivanti Policy Secure, and Ivanti Neurons. A remote attacker can trigger the flaw with crafted unauthenticated requests to the SAML component, causing the appliance to make requests to otherwise restricted resources. Successful exploitation allows the attacker to access certain restricted resources without any credentials, and CISA notes the flaw has been used in ransomware operations. Any organization running an affected Ivanti Connect Secure, Policy Secure, or Neurons deployment is exposed, particularly where the appliance is reachable from the internet. The vulnerability is confirmed exploited in the wild: it was added to CISA's Known Exploited Vulnerabilities catalog on 2024-01-31, carries an EPSS probability of 100%, and no public proof-of-concept is known.

Do: Apply Ivanti's released patches or the vendor-issued mitigations immediately per vendor instructions, or discontinue use of the product if mitigations are unavailable, as required by CISA. Because ransomware use is documented, review SAML-related logs and appliance audit trails for signs of exploitation and follow-on compromise, and check for indicators of post-exploitation activity. Monitor Ivanti advisories for patched version numbers and updated mitigation guidance, since specific fixed versions are not yet specified in the available data.