GHSA-w5hq-g745-h8pq

About vulnerability

Summary

v3, v5, and v6 accept external output buffers but do not reject out-of-range writes (small buf or large offset). By contrast, v4, v1, and v7 explicitly throw RangeError on invalid bounds.

This inconsistency allows silent partial writes into caller-provided buffers.

Affected code

• src/v35.ts (v3/v5 path) writes buf[offset + i] without bounds validation.
• src/v6.ts writes buf[offset + i] without bounds validation.

Reproducible PoC

cd /home/StrawHat/uuid
npm ci
npm run build

node --input-type=module -e "
import {v4,v5,v6} from './dist-node/index.js';
const ns='6ba7b810-9dad-11d1-80b4-00c04fd430c8';
for (const [name,fn] of [
['v4',()=>v4({},new Uint8Array(8),4)],
['v5',()=>v5('x',ns,new Uint8Array(8),4)],
['v6',()=>v6({},new Uint8Array(8),4)],
]) {
try { fn(); console.log(name,'NO_THROW'); }
catch(e){ console.log(name,'THREW',e.name); }
}"

Observed:

• v4 THREW RangeError
• v5 NO_THROW
• v6 NO_THROW

Example partial overwrite evidence captured during audit:

same true buf [
170, 170, 170, 170,
75, 224, 100,  63
]
v6 [
187, 187, 187, 187,
31,  19, 185,  64
]

Security impact

• Primary: integrity/robustness issue (silent partial output).
• If an application assumes full UUID writes into preallocated buffers, this can produce malformed/truncated/partially stale identifiers without error.
• In systems where caller-controlled offsets/buffer sizes are exposed indirectly, this may become a security-relevant logic flaw.

Suggested fix

Add the same guard used by v4/v1/v7:

if (offset < 0 || offset + 16 > buf.length) {
throw new RangeError(`UUID byte range ${offset}:${offset + 15} is out of buffer bounds`);
}

Apply to:

• src/v35.ts (covers v3 and v5)
• src/v6.ts

Affected product:

Next.js , Node.js , React , astro , aws-sdk , azure-sdk-for-js , blobs , browser-env , canvg , config-plugins , cordova-node-xcode , db0 , devtools , drizzle-orm , ember-cli , expo , expo-router , expo-sqlite , impound , jQuery , javascript-test-reporter , jayson , jest , jsdom , jspdf , last-release-npm , leek , libcipm , libnpm , loopback , loopback-connector , loopback-connector-remote , loopback-datasource-juggler , microsoft-authentication-library-for-js , ng-packagr , nitro , npm , npm-lifecycle , npm-registry-client , nuxt , prebuild-config , primitives , protractor , request , requestretry , sass-loader , semantic-release , sockjs , strong-remoting , styled-jsx , unimport , unplugin , unstorage , uuid , vite , vite-dev-rpc , vite-hot-client , vite-plugin-checker , vite-plugin-inspect , vite-plugin-vue , vite-plugin-vue-inspector , vite-plugin-vue-tracer , vitefu , webdriver-manager , webpack-dev-middleware , webpack-dev-server , webpack-log , window

Affected packages:

unplugin @ 3.2.0 (+370 more)

Summary

v3, v5, and v6 accept external output buffers but do not reject out-of-range writes (small buf or large offset). By contrast, v4, v1, and v7 explicitly throw RangeError on invalid bounds.

This inconsistency allows silent partial writes into caller-provided buffers.

Affected code

• src/v35.ts (v3/v5 path) writes buf[offset + i] without bounds validation.
• src/v6.ts writes buf[offset + i] without bounds validation.

Reproducible PoC

cd /home/StrawHat/uuid
npm ci
npm run build

node --input-type=module -e "
import {v4,v5,v6} from './dist-node/index.js';
const ns='6ba7b810-9dad-11d1-80b4-00c04fd430c8';
for (const [name,fn] of [
['v4',()=>v4({},new Uint8Array(8),4)],
['v5',()=>v5('x',ns,new Uint8Array(8),4)],
['v6',()=>v6({},new Uint8Array(8),4)],
]) {
try { fn(); console.log(name,'NO_THROW'); }
catch(e){ console.log(name,'THREW',e.name); }
}"

Observed:

• v4 THREW RangeError
• v5 NO_THROW
• v6 NO_THROW

Example partial overwrite evidence captured during audit:

same true buf [
170, 170, 170, 170,
75, 224, 100,  63
]
v6 [
187, 187, 187, 187,
31,  19, 185,  64
]

Security impact

• Primary: integrity/robustness issue (silent partial output).
• If an application assumes full UUID writes into preallocated buffers, this can produce malformed/truncated/partially stale identifiers without error.
• In systems where caller-controlled offsets/buffer sizes are exposed indirectly, this may become a security-relevant logic flaw.

Suggested fix

Add the same guard used by v4/v1/v7:

if (offset < 0 || offset + 16 > buf.length) {
throw new RangeError(`UUID byte range ${offset}:${offset + 15} is out of buffer bounds`);
}

Apply to:

• src/v35.ts (covers v3 and v5)
• src/v6.ts