FalkorDB up to 4.20.4 Ast /ast/ast_validations.c _ValidateUnion_Clauses stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.41+

Summaryinfo

A vulnerability identified as problematic has been detected in FalkorDB up to 4.20.4. Affected is the function _ValidateUnion_Clauses of the file /ast/ast_validations.c of the component Ast. This manipulation causes stack-based overflow. The identification of this vulnerability is CVE-2026-88406. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in FalkorDB up to 4.20.4. It has been declared as problematic. Affected by this vulnerability is the function _ValidateUnion_Clauses of the file /ast/ast_validations.c of the component Ast. The manipulation with an unknown input leads to a stack-based overflow vulnerability. The CWE definition for the vulnerability is CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). As an impact it is known to affect availability. The summary by CVE is:

FalkorDB (Redis module) v4.20.1 to v4.20.4 was discovered to contain a stack overflow in the _ValidateUnion_Clauses function (/ast/ast_validations.c). This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted input.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-88406 since 09/10/2026. The exploitation appears to be easy. The attack can be launched remotely. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/21/2026).

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

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/10/2026 CVE reserved
09/21/2026 +11 days Advisory disclosed
09/21/2026 +0 days VulDB entry created
09/21/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Not defined

CVE: CVE-2026-88406 (🔒)
GCVE (CVE): GCVE-0-2026-88406
GCVE (VulDB): GCVE-100-408319

Entryinfo

Created: 09/21/2026 23:58
Changes: 09/21/2026 23:58 (54)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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