sdelements Lets Chat up to 0.4.8 Mongoose Callback room null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$0-$5k2.67

Summaryinfo

A vulnerability labeled as problematic has been found in sdelements Lets Chat up to 0.4.8. The impacted element is an unknown function of the component Mongoose Callback Handler. Such manipulation of the argument room leads to null pointer dereference. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is listed as CVE-2026-66749. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in sdelements Lets Chat up to 0.4.8 and classified as problematic. Affected by this issue is an unknown part of the component Mongoose Callback Handler. The manipulation of the argument room with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. CVE summarizes:

Let's Chat 0.4.0 through 0.4.8 contains a null dereference vulnerability that allows authenticated attackers to crash the server by supplying a valid 24-character hex string room parameter that matches no document in the database. Attackers can send a crafted GET /messages request causing an uncaught TypeError in an asynchronous Mongoose callback that terminates the Node.js server process, with the same defect reachable through multiple code paths including the socket.io interface.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-66749 since 07/27/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit.

Applying the patch 617207ff3c0c0bf8e3c7a915bd9ec03f1dd8390c is able to eliminate this problem.

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Productinfo

Type

Vendor

Name

Version

Support

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
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: Null pointer dereference
CWE: CWE-476 / CWE-404
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: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 617207ff3c0c0bf8e3c7a915bd9ec03f1dd8390c

Timelineinfo

07/27/2026 CVE reserved
07/28/2026 +1 days Advisory disclosed
07/28/2026 +0 days VulDB entry created
07/28/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-66749 (🔒)
GCVE (CVE): GCVE-0-2026-66749
GCVE (VulDB): GCVE-100-383918

Entryinfo

Created: 07/28/2026 18:38
Changes: 07/28/2026 18:38 (58)
Complete: 🔍
Cache ID: 216::103

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