CVE-2025-6543

Memory overflow vulnerability leading to unintended control flow and Denial of Service

At a glance

Severity: CRITICAL 9.2
Exploitation: Known exploited (CISA KEV) · added 2025-06-30
Exploited per ENISA since 2025-06-30
EPSS: EPSS 10.43 % · percentile 96 (2026-10-27)
State: PUBLISHED
Published: 2025-06-25
Updated: 2026-02-26
Assigner: Citrix
NVD status: Analyzed

Description

Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server

Scores

Version	Score	Vector	Scored by
CVSS 4.0	CRITICAL 9.2	CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L	Citrix
CVSS 4.0	CRITICAL 9.2	CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD · secure@citrix.com (Secondary)
CVSS 3.1	CRITICAL 9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

CWE-119

European references

ENISA EUVD · EUVD-2025-19085
GCVE · GCVE-0-2025-6543

CERT-FR advisories

CERTFR-2025-AVI-0540 — Multiples vulnérabilités dans les produits Citrix · cert.ssi.gouv.fr
CERTFR-2025-ALE-009 — Multiples vulnérabilités dans Citrix NetScaler ADC et NetScaler Gateway · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:* ≥ 13.1 < 13.1-37.236
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:* ≥ 13.1 < 13.1-37.236
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* ≥ 13.1 < 13.1-59.19
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:* ≥ 14.1 < 14.1-47.46
cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* ≥ 13.1 < 13.1-59.19
cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:* ≥ 14.1 < 14.1-47.46

Affected products

Product	Versions
NetScaler · ADC	affected 14.1 < 47.46 ; affected 13.1 < 59.19 ; affected 13.1 FIPS and NDcPP < 37.236
NetScaler · Gateway	affected 14.1 < 47.46 ; affected 13.1 < 59.19 ; affected 13.1 FIPS and NDcPP < 37.236

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
CISA Known Exploited Vulnerabilities	CC0 1.0
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD