Description

A vulnerability was detected in wongcyrus ExcelLexBot up to 0.0.3. This affects the function ExcelLexBotS3TriggerFunction of the component Lambda Function Handler. Performing a manipulation results in improper privilege management. The attack may be initiated remotely. The vendor was contacted early about this disclosure but did not respond in any way. This vulnerability only affects products that are no longer supported by the maintainer.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.7",
  "pubDate": "2026-08-09T17:16:22.027Z",
  "pubdate": "2026-08-09T17:16:22.027Z",
  "executiveSummary": "An improper privilege management vulnerability has been identified in wongcyrus ExcelLexBot up to 0.0.3, specifically within the ExcelLexBotS3TriggerFunction component acting as a Lambda Function Handler. The flaw allows remote attackers to execute unauthorized actions due to insufficient access control and privilege enforcement mechanisms within the serverless execution environment. The risk implication is significant as it compromises the confidentiality, integrity, and availability of the affected cloud resources. The attack can be initiated remotely without requiring prior authentication, depending on the exposure of the trigger mechanism. Exploitation requirements are minimal assuming network reachability to the vulnerable AWS Lambda trigger interface. The vendor was contacted prior to disclosure and failed to respond, and the product remains unsupported by the maintainer, leaving systems deployed with this software permanently unpatched by the original author.",
  "technicalDetails": "The vulnerability stems from improper privilege management within the ExcelLexBotS3TriggerFunction of the Lambda Function Handler component in wongcyrus ExcelLexBot up to 0.0.3. The root cause is the failure to properly validate and restrict execution privileges and operational contexts when handling events within the serverless architecture. Specifically, the function executes tasks or processes inputs with overly permissive execution roles or without adequately scoping permissions associated with the AWS Lambda invocation or subsequent S3 bucket interactions. The affected component, ExcelLexBotS3TriggerFunction, handles events originating from cloud storage triggers, processing payloads that may be manipulated by remote actors if input validation and access controls are absent. The attack flow initiates when a remote attacker interacts with or supplies malicious payloads via the remote attack surface exposed by the service. Because the application lacks granular privilege management, the execution flow proceeds under an overly broad security context, granting the attacker the ability to perform operations outside their intended privilege boundary. Authentication and local privilege requirements are bypassed or non-existent due to the remote nature of the trigger vector, allowing unauthenticated remote invocation over standard cloud protocols. The post-exploitation impact includes unauthorized data access, modification, or potential lateral movement within the cloud infrastructure depending on the exact IAM permissions granted to the vulnerable Lambda execution role. Since the product is deprecated and no longer supported by the maintainer, internal code corrections via official vendor patches are unavailable."
}