CVE-2025-5456: 
Ivanti Connect Secure vulnerability analysis and mitigation

CVE-2025-5456 is a buffer over-read (out-of-bounds read) vulnerability affecting multiple Ivanti network security products that allows a remote unauthenticated attacker to trigger a denial of service condition. The vulnerability affects Ivanti Connect Secure before versions 22.7R2.8 or 22.8R2, Ivanti Policy Secure before 22.7R1.5, Ivanti ZTA Gateway before 2.8R2.3-723, and Ivanti Neurons for Secure Access before 22.8R1.4. It was published on August 12, 2025, with patches deployed for Neurons for Secure Access on August 2, 2025. The CVSS v3.1 base score is 7.5 (High) (Ivanti Advisory, Feedly).

The vulnerability is classified as CWE-125 (Out-of-bounds Read), corresponding to CAPEC-540 (Overread Buffers). An attacker can send a specially crafted network request to an affected Ivanti product without any authentication, causing the application to read memory beyond the bounds of an allocated buffer. This out-of-bounds read triggers a denial of service condition, likely through a crash or unhandled exception in the affected service. No authentication or user interaction is required, and the attack is conducted entirely over the network (Ivanti Advisory, Feedly).

Successful exploitation results in a denial of service condition on the affected Ivanti gateway or secure access product, potentially disrupting VPN, zero-trust access, and network policy enforcement for all users relying on the affected infrastructure. There is no impact to confidentiality or integrity — the vulnerability is limited to availability. Given that these products serve as critical network access control points, a sustained DoS attack could effectively block legitimate remote access for an entire organization (Ivanti Advisory, Feedly).

As of the time of publication, there is no public proof-of-concept exploit and no evidence of in-the-wild exploitation (Feedly). The EPSS score is approximately 0.235%, indicating a low probability of exploitation in the near term. The vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. No threat actor attribution has been reported. The low exploitation barrier — requiring no authentication or user interaction — does increase theoretical risk, particularly given Ivanti products' history of being targeted by sophisticated threat actors.

Ivanti has released patches addressing CVE-2025-5456 across all affected product lines. Organizations should upgrade to the following fixed versions as soon as possible:

• Ivanti Connect Secure: 22.7R2.8 or 22.8R2
• Ivanti Policy Secure: 22.7R1.5
• Ivanti ZTA Gateway: 2.8R2.3-723
• Ivanti Neurons for Secure Access: 22.8R1.4 (fix was deployed automatically on August 2, 2025)

For organizations unable to patch immediately, recommended interim mitigations include restricting network access to affected systems, implementing additional network segmentation, and deploying intrusion detection/prevention systems to monitor for anomalous traffic targeting these appliances (Ivanti Advisory).

The vulnerability was covered by several cybersecurity news outlets shortly after disclosure, including CyberPress, GBHackers, and CyberSecurityNews, primarily noting the DoS risk to Ivanti's widely deployed network access products. Black Kite included CVE-2025-5456 in its Focus Friday third-party risk management analysis, highlighting it as a concern for organizations relying on Ivanti infrastructure. Coverage was largely informational, with no significant controversy or notable researcher commentary beyond standard patch advisories (Ivanti Advisory).