CVE-2026-31827

HIGH

Alienbin <= 1.0.0 - Unauthenticated Denial of Service via TTL Index Race Condition

Title source: llm

Description

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.

References (1)

Core 1

Core References

Vendor Advisory x_refsource_confirm

https://github.com/Blue-B/Alienbin/security/advisories/GHSA-hqvr-6v89-gwff

Scores

CVSS v4 7.1

EPSS 0.0018

EPSS Percentile 7.9%

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-362

Status published

Products (1)

Blue-B/Alienbin <= 1.0.0

Published Mar 10, 2026

Tracked Since Mar 11, 2026