CVE-2025-5777

NetScaler ADC and NetScaler Gateway - Insufficient input validation leading to memory overread

HIGH

7.5

CVSS Score

Published: June 17, 2025 at 12:29 PM UTC

Updated: October 8, 2026 at 10:35 AM UTC

4 products affected across 2 vendorsNetScaler GatewayNetscaler Application Delivery ControllerADC

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Severity

HIGH7.5

Exploitation

CISA KEV

Exploit prediction

EPSS 100%

SSVC

Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score100.0%

EPSS (Exploit Prediction Scoring System) estimates a 100.0% chance this CVE is exploited in the wild within the next 30 days — higher than 100% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

Citrix NetScaler ADC and Gateway contain an out-of-bounds read vulnerability due to insufficient input validation. This vulnerability can lead to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server.

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.

Ransomware Use

Known

Added to KEV

Jul 10, 2025

Remediation Due

Jul 11, 2025

472 days overdue

Notes

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420

https://nvd.nist.gov/vuln/detail/CVE-2025-5777

Description

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

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Netscaler Application Delivery Controller · Citrix

95%

12.1 ≤ v < 12.1-55.32813.1 ≤ v < 13.1-37.23513.1 ≤ v < 13.1-58.3214.1 ≤ v < 14.1-43.56*

Affected range stops below 12.1-55.328, so it looks safe — our inference, not a vendor statement

Affected range stops below 13.1-37.235, so it looks safe — our inference, not a vendor statement

Affected range stops below 13.1-58.32, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1-43.56, so it looks safe — our inference, not a vendor statement

NetScaler Gateway · Citrix

95%

13.1 ≤ v < 13.1-58.3214.1 ≤ v < 14.1-43.56*

Affected range stops below 13.1-58.32, so it looks safe — our inference, not a vendor statement

Affected range stops below 14.1-43.56, so it looks safe — our inference, not a vendor statement

ADC · Netscaler

90%

13.1 ≤ v < 58.3214.1 ≤ v < 43.5613.1 14.1

Affected range stops below 43.56, so it looks safe — our inference, not a vendor statement

Affected range stops below 58.32, so it looks safe — our inference, not a vendor statement

Gateway · Netscaler

90%

13.1 ≤ v < 58.3214.1 ≤ v < 43.5613.1 14.1

Affected range stops below 43.56, so it looks safe — our inference, not a vendor statement

Affected range stops below 58.32, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420

References (10)

Vendor Advisory

Source: [email protected]

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX693420

Broken LinkThird Party Advisory