How severe is CVE-2026-88773?

CVE-2026-88773 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-88773 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-88773?

CVE-2026-88773 primarily affects Citrix Netscaler Application Delivery Controller. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-88773?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-88773 published?

CVE-2026-88773 was published on 2026-09-27 and last updated on 2026-09-29.

CVE-2026-88773

CVE-2026-88773 is a critical-severity vulnerability in Citrix Netscaler Application Delivery Controller with a CVSS 3.x base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-444.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
CVSS v4: 9.3
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Citrix Netscaler Application Delivery Controller
Published: 2026-09-27
Last modified: 2026-09-29

Description

Inconsistent interpretation of HTTP requests ('HTTP Request/Response smuggling') vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1-37.279 and NDcPP; Gateway: before 14.1-73.37 FIPS and before 13.1-64.23.

Frequently asked questions

What is CVE-2026-88773?: Inconsistent interpretation of HTTP requests ('HTTP Request/Response smuggling') vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1-37.279 and NDcPP; Gateway: before 14.1-73.37 FIPS and before 13.1-64.23.
How severe is CVE-2026-88773?: CVE-2026-88773 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-88773 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-88773?: CVE-2026-88773 primarily affects Citrix Netscaler Application Delivery Controller. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-88773?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-88773 published?: CVE-2026-88773 was published on 2026-09-27 and last updated on 2026-09-29.

References

https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX697096

Affected products (4)

cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:-:*:*:*
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:fips:*:*:*
cpe:2.3:a:citrix:netscaler_application_delivery_controller:*:*:*:*:ndcpp:*:*:*
cpe:2.3:a:citrix:netscaler_gateway:*:*:*:*:*:*:*:*

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