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Noroxi
NVD / CVE Program· CNA NetScaler

CVE-2026-8655: Multiple Memory overflow vulnerabilities leading to unpredictable or erroneous behavior and Denial of Service

Noroxi assessment

Priority: Monitor (action score 35/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.63% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: NetScaler ADC 37.272, 63.18, 72.61; NetScaler Gateway 63.18, 72.61.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to NetScaler ADC 37.272, 63.18, 72.61; NetScaler Gateway 63.18, 72.61 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Multiple Memory overflow vulnerabilities in NetScaler ADC and NetScaler Gateway leading to unpredictable or erroneous behavior and Denial of Service if NetScaler ADC is configured as an LB of type Oracle OR NetScaler ADC is configured as a DNS Proxy OR NetScaler ADC is configured as a DNS recursive resolver deployment

HighCVSS 8.8 · v4.0—No exploit Fix available
Published
Jun 30, 2026
Updated
Jul 1, 2026
EPSS
0.6% · 49th percentile

Report tools

JSON

Action score

35

Monitor

Low priority for now.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · NetScaler
8.8
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:L

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-8655

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
citrixnetscaler application delivery controller
citrixnetscaler gateway

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • citrix netscaler gateway13.1 and later · before 13.1-63.18
  • citrix netscaler gateway14.1 and later · before 14.1-72.61

Versions reported by the vendor

Affected version ranges reported by the assigning authority (NetScaler). Independent of NVD's CPE analysis and usually ahead of it.

  • NetScaler ADC

    • 14.1 and later · before 72.61affected · patch
    • 13.1 and later · before 63.18affected · patch
    • 14.1 FIPS and later · before 72.61affected · patch
    • 13.1 FIPS and NDcPP and later · before 37.272affected · patch

  • NetScaler Gateway

    • 14.1 and later · before 72.61affected · patch
    • 13.1 and later · before 63.18affected · patch

Same product

citrix: all records

Other highest-scoring records for the same primary product.

  • CVE-2023-3519Unauthenticated remote code executionKEV
    99Now
  • CVE-2025-5777NetScaler ADC and NetScaler Gateway - Insufficient input validation leading to memory overreadKEV
    97Now
  • CVE-2026-3055Insufficient input validation leading to memory overreadKEV
    94Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-8451Jun 30, 2026 · Insufficient input validation leading to memory overread
    35Monitor
  • ← EarlierCVE-2026-8452Jun 30, 2026 · Memory overflow vulnerability leading to unpredictable or erroneous behavior and Denial of ServiceKEV
    65This week
  • Later →CVE-2026-19490Aug 19, 2026 · NetScaler ADC and NetScaler Gateway Security Bulletin for CVE-2026-19490KEV
    77This week

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
NetScaler ADC37.272Vendor (CNA)
NetScaler ADC63.18Vendor (CNA)
NetScaler ADC72.61Vendor (CNA)
NetScaler Gateway63.18Vendor (CNA)
NetScaler Gateway72.61Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-8877289 days apartMemory overflow vulnerability leading to Remote Code Execution or Denial of ServiceKEV
    91Now
  • CVE-2025-7775308 days apartMemory overflow vulnerability leading to Remote Code Execution and/or Denial of ServiceKEV
    72This week
  • CVE-2025-6543370 days apartMemory overflow vulnerability leading to unintended control flow and Denial of ServiceKEV
    69This week
  • CVE-2026-8877996 days apartMemory overflow vulnerability leading to Denial of ServiceKEV
    67This week
  • CVE-2026-84520 days apartMemory overflow vulnerability leading to unpredictable or erroneous behavior and Denial of ServiceKEV
    65This week
  • CVE-2025-7776308 days apartMemory overflow vulnerability leading to unpredictable or erroneous behavior and Denial of Service
    38Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records