What is CVE-2025-5777?

CVE-2025-5777 is a high-severity vulnerability in Citrix Netscaler_application_delivery_controller, classified under Out-of-bounds Read. CVSS score: 7.5/10. Published 2025-06-17.

How severe is CVE-2025-5777?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2025-5777 known to be exploited?

Yes. CVE-2025-5777 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-07-10), indicating it is being actively exploited. 47 public proof-of-concept repositories are indexed.

Out-of-bounds Read in Citrix Netscaler_application_delivery_controller

CVE-2025-5777

Insufficient input validation leading to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server

Vulnerability class: Buffer Overflow

EPSS: 0.999 (100.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Citrix Netscaler_application_delivery_controller
Citrix Netscaler_gateway
Netscaler Adc — versions 14.1, 13.1
Netscaler Gateway — versions 14.1, 13.1

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2025-07-10. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2025-07-11.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

secure@citrix.com (Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Broken Link, Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Press/Media Coverage, Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Press/Media Coverage)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)

Frequently asked questions

What is CVE-2025-5777?: CVE-2025-5777 is a high-severity vulnerability in Citrix Netscaler_application_delivery_controller, classified under Out-of-bounds Read. CVSS score: 7.5/10. Published 2025-06-17.
How severe is CVE-2025-5777?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-5777 known to be exploited?: Yes. CVE-2025-5777 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-07-10), indicating it is being actively exploited. 47 public proof-of-concept repositories are indexed.