CVE-2026-31827

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Blue-BAlienbin<= 1.0.0affected

Weaknesses

  • CWE-362: CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References