# CVE-2026-53496: ExifReader denial of service via uncaught RangeError in ISO-BMFF parser

Source: https://junglewise.ai/threats/cve-2026-53496-exifreader-denial-of-service-via-uncaught-rangeerror-in-iso-bmff  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-14. Updated: 2026-07-17  
License: CC BY 4.0 with a link back

CVE-2026-53496 · Severity: medium · CVSS 5.3 · Published 2026-09-14

ExifReader is a library used by applications to extract metadata from image files. A vulnerability in how it handles HEIC and AVIF images allows an attacker to provide a specially crafted image that causes the application to crash. This can lead to a denial-of-service, potentially disrupting image processing workflows or taking down web services that handle user uploads.

Technologies: [Mattias Wadstein ExifReader](https://junglewise.ai/threats/technologies/exifreader), [exifreader (npm)](https://junglewise.ai/threats/technologies/npm-exifreader). Vendors: [Mattias Wadstein](https://junglewise.ai/threats/vendors/mattias-wadstein), [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-53496 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-53496 being exploited in the wild.

**How severe is CVE-2026-53496?** Medium severity, with a CVSS score of 5.3, published 14 September 2026.

**Which products and versions are affected?** Mattias Wadstein ExifReader <= 4.40.0; exifreader (npm) SEMVER:introduced=0,fixed=4.40.1.

**Is there a fix for CVE-2026-53496?** Yes. exifreader (npm): upgrade to 4.40.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-53496 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-53496?** Check whether you run Mattias Wadstein ExifReader or exifreader (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- exifreader (npm): upgrade to 4.40.1 or later

  ```sh
  npm install exifreader@4.40.1
  ```


## Technical details

ExifReader (up to version 4.40.0) contains an uncaught RangeError in its ISO-BMFF parser used for HEIC and AVIF files. The root cause is a lack of bounds checking in `src/image-header-iso-bmff.js` within the `findMetaBox`, `parseBox`, and `getBoxLength` functions. Specifically, the parser unconditionally reads fields (such as the full-box version byte or 64-bit extended size) without verifying that the DataView buffer contains sufficient bytes. An attacker can trigger this by providing a truncated or malformed ISO-BMFF box following a valid `ftyp` box, leading to an unhandled exception that can crash the Node.js process or worker thread. This is fixed in version 4.40.1.

## Affected products

- mattiasw exifreader <= 4.40.0

## Identifiers

- CVE-2026-53496
- GHSA-g77h-45rf-hcx4

## Timeline

- 2026-06-06: disclosed: Vulnerability reported to vendor
- 2026-07-17: advisory: GitHub Advisory published
- 2026-07-17: patched: Version 4.40.1 released

## References

- [https://api.github.com/users/YHalo-wyh](https://api.github.com/users/YHalo-wyh)
- [https://github.com/YHalo-wyh](https://github.com/YHalo-wyh)
- [https://api.github.com/users/YHalo-wyh/gists%7B/gist_id%7D](https://api.github.com/users/YHalo-wyh/gists%7B/gist_id%7D)
- [https://api.github.com/users/YHalo-wyh/repos](https://api.github.com/users/YHalo-wyh/repos)
- [https://avatars.githubusercontent.com/u/206865908?v=4](https://avatars.githubusercontent.com/u/206865908?v=4)
- [https://api.github.com/users/YHalo-wyh/events%7B/privacy%7D](https://api.github.com/users/YHalo-wyh/events%7B/privacy%7D)

## Related threats

- [ExifReader denial of service via crafted HEIC/AVIF iloc box](https://junglewise.ai/threats/cve-2026-85715-exifreader-denial-of-service-via-crafted-heic-avif-iloc-box)
- [ExifReader data amplification in PNG zTXt metadata decompression](https://junglewise.ai/threats/cve-2026-8814-exifreader-data-amplification-in-png-ztxt-metadata-decompression)
- [ExifReader denial of service via memory exhaustion in ICC mluc tag parsing](https://junglewise.ai/threats/cve-2026-8813-exifreader-denial-of-service-via-memory-exhaustion-in-icc-mluc-tag)