CVE-2023-6549

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.576 · 99 %ileDEEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV

Likely / severe?

57.6% (99th) EPSS

CVSS 7.5 · high

Is it mine?

20 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2024-01-17remediate by 2024-02-07

required action Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

EPSS · scored 2026-10-25

Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability

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

Technical severity, 0–10. One row per scoring source.

8.2

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.18.2highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Hsecondary · FSTEC (BDU) RU

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Hsecondary · ENISA EU

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Hsecondary · secure@citrix.comexploitability 3.9 · impact 4.2

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-119USprimaryCWE-119USCWE-94US

ATT&CK techniques

ATT&CK techniques this enables or maps to.

affected products (20)

Products and version ranges known to be affected.

Cloud Software Group NetScaler ADC12.1-FIPS → 55.302enisa_euvdEU
Cloud Software Group NetScaler ADC12.1-NDcPP → 55.302enisa_euvdEU
Cloud Software Group NetScaler ADC13.0 → 92.21enisa_euvdEU
Cloud Software Group NetScaler ADC13.1 → 51.15enisa_euvdEU
Cloud Software Group NetScaler ADC13.1-FIPS → 37.176enisa_euvdEU
Cloud Software Group NetScaler ADC14.1 → 12.35enisa_euvdEU
Citrix Systems Inc. NetScaler Application Delivery Controller13.0 → 13.0-92.21fstec_bduRU
Citrix Systems Inc. NetScaler Application Delivery Controller13.1 → 13.1-51.15fstec_bduRU
Citrix Systems Inc. NetScaler Application Delivery Controller14.1 → 14.1-12.35fstec_bduRU
Citrix Systems Inc. NetScaler Gateway13.0 → 13.0-92.21fstec_bduRU
Citrix Systems Inc. NetScaler Gateway13.1 → 13.1-51.15fstec_bduRU
Citrix Systems Inc. NetScaler Gateway14.1 → 14.1-12.35fstec_bduRU
citrix netscaler application delivery controller12.1 → 12.1-55.302nvdUScpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:*:*:*:*
citrix netscaler application delivery controller13.0 → 13.0-92.21nvdUScpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:*:*:*:*
citrix netscaler application delivery controller13.1 → 13.1-37.176nvdUScpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:*:*:*:*
citrix netscaler application delivery controller13.1 → 13.1-51.15nvdUScpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:*:*:*:*
citrix netscaler application delivery controller14.1 → 14.1-12.35nvdUScpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:*:*:*:*
citrix netscaler gateway13.0 → 13.0-92.21nvdUScpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:*
citrix netscaler gateway13.1 → 13.1-51.15nvdUScpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:*
citrix netscaler gateway14.1 → 14.1-12.35nvdUScpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-0133Citrix Systems Produkte: Mehrere SchwachstellenDeutsch2024-01-16csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Citrix Systems ADC und Citrix Systems Citrix Gateway ausnutzen, um beliebigen Programmcode auszuführen oder einen Denial of Service zu verursachen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd cert_bund NVD CVE.org MITRE

published 2024-01-17modified 2026-06-17

related (21,008)

Related entries.

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+21003 more

references (8)

External citations — patches, advisories, analysis.

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