CVE-2025-6543 (GCVE-0-2025-6543)

Vulnerability from cvelistv5 – Published: 2025-06-25 12:49 – Updated: 2025-10-21 22:45
VLAI? CISA ENISA
Summary
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
Severity ?
9.2 (Critical)
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
CWE
  • CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer
Assigner
References
Impacted products
Vendor Product Version
NetScaler ADC Affected: 14.1 , < 47.46 (patch)
Affected: 13.1 , < 59.19 (patch)
Affected: 13.1 FIPS and NDcPP , < 37.236 (patch)
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    NetScaler Gateway Affected: 14.1 , < 47.46 (patch)
Affected: 13.1 , < 59.19 (patch)
Affected: 13.1 FIPS and NDcPP , < 37.236 (patch)
Create a notification for this product.
CISA Known Exploited Vulnerability
Data from the CISA Known Exploited Vulnerabilities Catalog

Date added: 2025-06-30

Due date: 2025-07-21

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.

Used in ransomware: Unknown

Notes: https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX694788 ; https://www.netscaler.com/blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-2025-5777/ ; https://nvd.nist.gov/vuln/detail/CVE-2025-6543

ENISA Known Exploited Vulnerability
Data from the ENISA CNW Known Exploited Vulnerabilities Catalog
Vendor/Product: Citrix | Product: Citrix ADC and Citrix Gateway

CVE: CVE-2025-6543

EUVD: EUVD-2025-19085

Date reported: 18/07/25

Show details on NVD website
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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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