CVE-2026-8814: ExifReader is vulnerable to denial of service via unbounded decompression of image metadata

Versions of ExifReader from 4.20.0 through 4.38.1 do not bound the size of decompressed metadata blocks. When a caller invokes the asynchronous API (e.g. ExifReader.load(file) or ExifReader.load(buffer, {async: true})) on an attacker-supplied image, a small compressed chunk in the file can expand to hundreds of megabytes of memory, consuming heap and CPU until the process slows down or runs out of memory.

The affected paths share a single decompression utility, so the issue is reachable through any compressed metadata block the library handles asynchronously, including:

• PNG zTXt, compressed iTXt, and iCCP chunks (deflate)
• JPEG XL Brotli-compressed Exif and XMP blocks

A typical proof of concept produced roughly 1000× expansion (for example, ~32 KB of compressed input expanded to ~32 MB of output, ~130 KB to ~128 MB).

Both the npm package and the dist/ bundle published from this repository (consumed by Bower and other users of the prebuilt artifact) are affected.