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CVE-2023-3519· NVD / CVE Program· CNA Citrix

Unauthenticated remote code execution

Noroxi assessment

Priority: Now (action score 99/100)

  • CISA has confirmed exploitation in the wild (Jul 19, 2023); it is known to be used in ransomware campaigns. Remediation deadline for US federal agencies: Aug 9, 2023.
  • A ready-made attack module is public (Metasploit, Nuclei); exploiting it takes no special expertise.
  • Probability of exploitation in the next 30 days: 99.7% (FIRST EPSS); higher than 99.9% of all records.
  • 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.
  • Fixed version: Citrix NetScaler ADC 37.159, 49.13, 55.297; Citrix NetScaler Gateway 49.13, 91.13.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Patch today or shut off access. Upgrade to Citrix NetScaler ADC 37.159, 49.13, 55.297; Citrix NetScaler Gateway 49.13, 91.13 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 · CISA KEV · FIRST EPSS

CriticalCVSS 9.8 · v3.1KEVWeaponized Fix available
Published
Jul 19, 2023
Updated
Aug 5, 2026
EPSS
99.7% · 99th percentile

Report tools

JSON

Action score

99

Now

Patch today or shut off access.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
30 / 30 · Listed
EPSS
30 / 30 · 99.7%

CISA SSVC decision

Exploitation
active
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
9.8
CNA · Citrix
9.8
agree

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

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Jul 19, 2023. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Aug 9, 2023.

Known to be used in ransomware campaigns.

Get told when this record changes

  • In CISA KEV: exploitation in the wild confirmed
  • Weaponized exploit exists
  • A fix has been released

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

Follow CVE-2023-3519

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

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

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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 gateway13.0 and later · before 13.0-91.13
  • citrix netscaler gateway13.1 and later · before 13.1-49.13

Versions reported by the vendor

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

  • Citrix NetScaler ADC

    • 13.1 and later · before 49.13affected · patch
    • 13.0 and later · before 91.13affected · patch
    • 13.1-FIPS and later · before 37.159affected · patch
    • 12.1-FIPS and later · before 55.297affected · patch
    • 12.1-NDcPP and later · before 55.297affected · patch
  • Citrix NetScaler Gateway

    • 13.1 and later · before 49.13affected · patch
    • 13.0 and later · before 91.13affected · patch

Other highest-scoring records for the same primary product.

  • CVE-2025-5777NetScaler ADC and NetScaler Gateway - Insufficient input validation leading to memory overreadKEV
    97Now
  • CVE-2023-4966Unauthenticated sensitive information disclosureKEV
    90Now
  • CVE-2023-6549Improper Restriction of Operations within the Bounds of a Memory Buffer in NetScaler ADC and NetScaler Gateway allows Unauthenticated DenialKEV
    77This week

Published before and after this one in the same product

  • ← EarlierCVE-2016-2072Feb 17, 2016 · The Administrative Web Interface in Citrix NetScaler Application Delivery Controller (ADC) and NetScaler Gateway 11.x before 11.0 Build 64.3
    24Monitor
  • ← EarlierCVE-2018-5314Mar 1, 2018 · Command injection vulnerability in Citrix NetScaler ADC and NetScaler Gateway 11.0 before build 70.16, 11.1 before build 55.13, and 12.0 bef
    31Monitor
  • Later →CVE-2023-3466Jul 19, 2023 · Reflected Cross-Site Scripting (XSS)
    25Monitor

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
Citrix NetScaler ADC37.159Vendor (CNA)
Citrix NetScaler ADC49.13Vendor (CNA)
Citrix NetScaler ADC55.297Vendor (CNA)
Citrix NetScaler ADC91.13Vendor (CNA)
Citrix NetScaler Gateway49.13Vendor (CNA)
Citrix NetScaler Gateway91.13Vendor (CNA)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

  • Metasploit module ×1
  • Nuclei detection template ×1
  • Proof-of-concept repository on GitHub ×13

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Nuclei detection templateNuclei template CVE-2023-3519 —
Proof-of-concept repository on GitHubstars:12023-08-05
Proof-of-concept repository on GitHubstars:12023-08-06
Proof-of-concept repository on GitHubstars:652023-08-10
Proof-of-concept repository on GitHubstars:52023-08-24
Metasploit moduleexploit/freebsd/http/citrix_formssso_target_rceCitrix ADC (NetScaler) Forms SSO Target RCEexploit2023-07-18
Proof-of-concept repository on GitHubstars:542023-07-20
Proof-of-concept repository on GitHubstars:962023-07-20
Proof-of-concept repository on GitHubstars:132023-07-21
Proof-of-concept repository on GitHubstars:02023-07-21
Proof-of-concept repository on GitHubstars:2282023-07-21
Proof-of-concept repository on GitHubstars:112023-07-21

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.

  1. Metasploit-2 d
  2. CISA KEV-1 d
  3. Published
  4. First PoCsame day
  5. TodayOct 24, 2026+1193 d
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.

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.

No nightly-computed relations.

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
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Change log

  1. Fix✗ → ✓

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

References

All records