CVE-2026-53496 ExifReader HEIC/AVIF ISO-BMFF parser throws uncaught RangeError on truncated boxes
Attackers can cause denial of service in applications using ExifReader by supplying malformed HEIC or AVIF images that trigger uncaught errors.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53496?
CVE-2026-53496 is a medium-severity denial of service vulnerability in mattiasw ExifReader, published on 14 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ExifReader is a JavaScript Exif information parser. Prior to 4.40.1, ExifReader.load() and the asynchronous file and URL loaders can pass attacker-supplied HEIC or AVIF data to the ISO-BMFF parser in src/image-header-iso-bmff.js, where findMetaBox() and parseBox() accept an eight-byte box header without confirming that fields required by the parsed box remain in the DataView. A valid ftyp box followed by an empty free or unknown box can cause an unchecked full-box version read, while a truncated extended-size box can make getBoxLength() and hasEmptyHighBits() read absent size fields. The resulting RangeError escapes the main parsing path and can abort an application request or worker when parse errors are not defensively caught, causing denial of service. This issue is fixed in version 4.40.1.
Which versions are affected by CVE-2026-53496?
2 open source packages ship an affected version, including exifreader.
| Package | Affected | Fixed in |
|---|---|---|
exifreader npm | All versions | 4.40.1 |
exifreader npm | All versions | 4.40.1 |
How do I fix CVE-2026-53496?
Upgrade exifreader to 4.40.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-53496 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-53496 exists.
Sources
Also known as GHSA-g77h-45rf-hcx4.