High severity · published Jan 17, 2024
CVE-2023-6549
Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability
In wildKEV
7.5
CVSS
57.6%
EPSS
Yes
On KEV
Description
Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated Denial of Service and Out-Of-Bounds Memory Read
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)57.6% · higher than 99% of CVEs
Exploited in the wildYes
CISA KEVListed Jan 17, 2024
Federal remediation dueFeb 7, 2024
Ransomware campaign useNot known
Affected products
Which versions
NA
NetScaler ADC · Citrix
12.1 before 12.1-55.302; 12.1 before 12.1-55.302; 13.0 before 13.0-92.21; 13.1 before 13.1-37.176; 13.1 before 13.1-51.15; 14.1 before 14.1-12.35 · source: NVD, vendor
NA
NetScaler ADC and NetScaler Gateway · Citrix
All versions, or not specified · source: KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-6549
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-6549
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
support.citrix.com
https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549
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