CVE Catalog

CVE-2026-31827

High
Published: Translated: NVD NIST

Summary

Alienbin is a web service for anonymous code and text sharing. In version 1.0.0 and earlier, the /save endpoint in server.js drops and recreates the MongoDB TTL index on the entire post collection for every new paste submission. When User B submits a paste with a short TTL (e.g., 30 seconds), the TTL index is recreated with expireAfterSeconds: 30 for all documents, causing User A's paste (originally set to 7 days) to be deleted after 30 seconds.

Risk Assessment

An attacker can intentionally delete all existing pastes by repeatedly submitting pastes with ttlOption=30s, leading to data loss and service disruption.

Recommendation

Immediately update Alienbin to a version newer than 1.0.0 if available, or apply a patch that prevents recreating the TTL index on every submission. Also consider restricting the ability to set very short TTL values.

Related vulnerabilities

Original NVD description (English source)

Alienbin is an anonymous code and text sharing web service. In 1.0.0 and earlier, the /save endpoint in server.js drops and recreates the MongoDB TTL index on the entire post collection for every new paste submission. When User B submits a paste with a short TTL (e.g., 30 seconds), the TTL index is recreated with expireAfterSeconds: 30 for all documents in the collection. This causes User A's paste (originally set to 7 days) to be deleted after 30 seconds. An attacker can intentionally delete all existing pastes by repeatedly submitting pastes with ttlOption=30s.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS