Citrix NetScaler ADC/NetScaler Gateway Base64 Decoding buffer overflow

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.9$5k-$25k0.00+

Summaryinfo

A vulnerability has been found in Citrix NetScaler ADC and NetScaler Gateway and classified as very critical. Affected by this issue is some unknown functionality of the component Base64 Decoding. Performing a manipulation results in buffer overflow. This vulnerability is known as CVE-2026-111337. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as very critical has been found in Citrix NetScaler ADC and NetScaler Gateway (the affected version unknown). This affects an unknown part of the component Base64 Decoding. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Memory overflow in Base64 decoding in advanced policy expressions leading to unpredictable or erroneous behavior or Denial of Service in Citrix NetScaler ADC and Citrix NetScaler Gateway.

It is possible to read the advisory at support.citrix.com. This vulnerability is uniquely identified as CVE-2026-111337 since 10/15/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/13/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.9

VulDB Base Score: 9.9
VulDB Temp Score: 9.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

10/15/2026 CVE reserved
11/13/2026 +29 days Advisory disclosed
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: citrix.com

Advisory: support.citrix.com
Status: Not defined

CNA: NetScaler
CVE: CVE-2026-111337 (🔒)

GCVE (CVE): GCVE-0-2026-111337
GCVE (VulDB): GCVE-100-436635

Entryinfo

Created: 11/13/2026 08:54
Changes: 11/13/2026 08:54 (64)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you want to use VulDB in your project?

Use the official API to access entries easily!