CVE-2025-7775 — Citrix NetScaler Memory Overflow Vulnerability
Memory overflow vulnerability leading to Remote Code Execution and/or Denial of Service in NetScaler ADC and NetScaler Gateway when NetScaler is configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server (OR) NetScaler ADC and NetScaler Gateway 13.1, 14.1, 13.1-FIPS and NDcPP: LB virtual servers of type (HTTP, SSL or HTTP_QUIC) bound with IPv6 services or servicegroups bound with IPv6 servers (OR) NetScaler ADC and NetScaler Gateway 13.1, 14.1, 13.1-FIPS and NDcPP: LB virtual servers of type (HTTP, SSL or HTTP_QUIC) bound with DBS IPv6 services or servicegroups bound with IPv6 DBS servers (OR) CR virtual server with type HDX
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Confirmed exploitation (CISA KEV)+35
- Public exploit/PoC (github)+6
- EPSS 20.3% (30-day exploitation probability)+15
- Technical severity (critical)+10
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
CISA required action CISA
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
US federal deadline: Aug 28, 2025 — passed 413 day(s) ago
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Citrix Netscaler Application Delivery Controller, Citrix Netscaler Gateway, NetScaler ADC…).
- Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- EPSS ahead of 97% of scored CVEs: prioritize it in the patch queue.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Citrix | Netscaler Application Delivery Controller | ≥ 12.1 and < 12.1-55.330≥ 13.1 and < 13.1-37.241≥ 13.1 and < 13.1-59.22≥ 14.1 and < 14.1-47.48 | Vulnerable | NIST National Vulnerability Database |
| Citrix | Netscaler Gateway | ≥ 13.1 and < 13.1-59.22≥ 14.1 and < 14.1-47.48 | Vulnerable | NIST National Vulnerability Database |
| NetScaler | ADC | ≥ 14.1 and < 47.48≥ 13.1 and < 59.22≥ 13.1 FIPS and NDcPP and < 37.241≥ 12.1 FIPS and NDcPP and < 55.330 | Vulnerable | CVE Program (cve.org) e CISA ADP |
| NetScaler | Gateway | ≥ 14.1 and < 47.48≥ 13.1 and < 59.22≥ 13.1 FIPS and NDcPP and < 37.241≥ 12.1 FIPS and NDcPP and < 55.330 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 9.2 | CVSS 4.0 | Critical | — | — | secure@citrix.com via NIST National Vulnerability Database |
| 9.2 | CVSS 4.0 | Critical | — | — | Citrix via CVE Program (cve.org) e CISA ADP |
| 9.8 | CVSS 3.1 | Critical | 3.9 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 9.8 | CVSS 3.1 | Critical | — | — | GitHub, Inc. via GitHub Security Advisories |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CWE-119 · Buffer Errors (Improper Restriction of Operations within Memory Bounds)
CISA KEV details CISA
CISA lists a CVE once it has evidence of exploitation against real targets.
CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.
Public exploits, PoCs and detection templates
Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.
- swabird/CVE-2025-7775-PoC ★ 4 Aug 28, 2025
- Detection for CVE-2025-7775 ★ 2 Aug 31, 2025
- Version detection PowerShell ★ 1 Sep 2, 2025
- Aaqilyousuf/CVE-2025-7775-vulnerable-lab ★ 0 Aug 30, 2025
Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.
EPSS over time FIRST
Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 20.28%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
- Hunt retroactively in logs from before Aug 26, 2025 (KEV listing): exploitation may have started earlier.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · netscaler/adc, netscaler/gateway
- SSVC assessment updated
- Record published
- Affected products added · citrix/netscaler application delivery controller, citrix/netscaler gateway
- CVSS changed · 9.8
- Source status changed · → Analyzed
- Added to CISA KEV (detected)
- Record created in this database
- 2025
- CVE published
- Added to CISA KEV catalog
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 13, 2026 – Oct 13, 2026
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
4 on the record
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-107406 Memory overflow vulnerability leading to Remote Code Execution or Denial of Service 6d
- High CVE-2026-88779 Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability KEV 11d
- High CVE-2026-88772 Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability KEV 18d
- Critical CVE-2026-88771 Citrix NetScaler Improper Input Validation Vulnerability KEV 18d
- Critical CVE-2026-19490 Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability KEV Aug 19, 2026
- Critical CVE-2026-8655 Multiple Memory overflow vulnerabilities leading to unpredictable or erroneous behavior and Denial of Service Jun 30, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-7775 is "Citrix NetScaler Memory Overflow Vulnerability", rated Critical. It affects Netscaler Application Delivery Controller (Citrix); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 9.8 describes technical severity. EPSS 20.28% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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