CVE-2026-73086

Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Bitbucket, Confluence, Fisheye/Crucible, Jira Software und Jira Service Management ausnutzen, um beliebigen Programmcode auszuführen, Sicherheitsmaßnahmen zu umgehen, serverseitige Request-Forgery-Angriffe (SSRF) durchzuführen, Cross-Site-Scripting-Angriffe zu starten, sensible Informationen offenzulegen, Daten zu manipulieren oder Denial-of-Service-Zustände herbeizuführen.

Ein Angreifer kann mehrere Schwachstellen in HCL BigFix ausnutzen, um Sicherheitsmaßnahmen zu umgehen, erweiterte Berechtigungen zu erlangen, beliebigen Code auszuführen, Daten offenzulegen oder zu manipulieren, SQL-Injection- oder Cross-Site-Scripting-Angriffe durchzuführen oder serverseitige Request-Forgery- sowie Brute-Force- und Session-Hijacking-Angriffe auszuführen.

Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Bitbucket, Confluence, Crucible, Fisheye und Jira ausnutzen, um Daten zu manipulieren, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um einen Cross-Site Scripting Angriff durchzuführen, um Sicherheitsvorkehrungen zu umgehen und um beliebigen Programmcode auszuführen.

### Summary An integer overflow in `nanoid(size)` permanently corrupts the process-wide CSPRNG pool, causing all subsequent ID generation to return the deterministic string `"uuuuuuuuuuuuuuuuuuuuu"`. Any application that passes user-influenced values to the `size` parameter loses all randomness guarantees for session tokens, CSRF tokens, and unique identifiers until process restart. ### Details `nanoid()` at [`index.js:101`](https://github.com/ai/nanoid/blob/main/index.js#L101) coerces the `size` parameter with `size |= 0`, which converts it to a signed 32-bit integer. When `size >= 2^31` (e.g., `2147483648`), this wraps to `-2147483648`. The negative value is passed to `fillPool()` ([`index.js:15`](https://github.com/ai/nanoid/blob/main/index.js#L15)): ```javascript function fillPool(bytes) { if (!pool || pool.length < bytes) { // false: pool exists, -2B < pool.length pool = Buffer.allocUnsafe(bytes * POOL_SIZE_MULTIPLIER) crypto.getRandomValues(pool) poolOffset = 0 } else if (poolOffset + bytes > pool.length) { // false: poolOffset + (-2B) < pool.length crypto.getRandomValues(pool) poolOffset = 0 } poolOffset += bytes // poolOffset += -2147483648 → deeply negative } ``` Neither branch triggers, so the pool is never refreshed. `poolOffset` becomes ~-2.1 billion. Subsequent `nanoid()` calls execute: ```javascript for (let i = poolOffset - size; i < poolOffset; i++) { id += scopedUrlAlphabet[pool[i] & 63] } ``` `pool[negative_index]` returns `undefined`. `undefined & 63` evaluates to `0`. `urlAlphabet[0]` is `'u'`. Every ID becomes `"uuuuuuuuuuuuuuuuuuuuu"`. The corruption is **persistent** — it affects all subsequent calls in the process until ~100 million calls eventually wrap `poolOffset` back to positive, or the process restarts. ### PoC ```javascript import { nanoid } from 'nanoid' // Step 1: Normal operation console.log(nanoid()) // e.g., "V1StGXR8_Z5jdHi6B-myT" // Step 2: Trigger overflow (e.g., from an API parameter) try { nanoid(2147483648) } catch(e) {} // Step 3: All subsequent IDs are deterministic console.log(nanoid()) // "uuuuuuuuuuuuuuuuuuuuu" console.log(nanoid()) // "uuuuuuuuuuuuuuuuuuuuu" console.log(nanoid()) // "uuuuuuuuuuuuuuuuuuuuu" // ... forever, process-wide ``` Run with: `node --experimental-vm-modules poc.mjs` Attack scenario: Any API endpoint that accepts a user-controlled length/size parameter (URL shortener slug length, configurable token size, etc.) and passes it to `nanoid(userInput)`. ### Impact **Complete loss of ID unpredictability and uniqueness, process-wide, from a single request.** - All session IDs, CSRF tokens, API keys, and database identifiers generated after the attack are identical and predictable - An attacker can predict all tokens issued to other users, enabling session hijacking and authentication bypass - The corruption is persistent (survives across requests) and affects all consumers of `nanoid` in the same process - No special privileges or preconditions required — a single unauthenticated request is sufficient - Affects any application that passes external input to the `size` parameter without validation