CVE-2026-24738 gmrtd ReadFile Vulnerable to Denial of Service via Excessive TLV Length Values
A malicious NFC tag can cause denial of service in applications using the gmrtd library by sending excessive TLV length values, leading to resource exhaustion.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-24738?
CVE-2026-24738 is a medium-severity denial of service vulnerability in gmrtd, published on 27 Jan 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
gmrtd is a Go library for reading Machine Readable Travel Documents (MRTDs). Prior to version 0.17.2, ReadFile accepts TLVs with lengths that can range up to 4GB, which can cause unconstrained resource consumption in both memory and cpu cycles. ReadFile can consume an extended TLV with lengths well outside what would be available in ICs. It can accept something all the way up to 4GB which would take too many iterations in 256 byte chunks, and would also try to allocate memory that might not be available in constrained environments like phones. Or if an API sends data to ReadFile, the same problem applies. The very small chunked read also locks the goroutine in accepting data for a very large number of iterations. projects using the gmrtd library to read files from NFCs can experience extreme slowdowns or memory consumption. A malicious NFC can just behave like the mock transceiver described above and by just sending dummy bytes as each chunk to be read, can make the receiving thread unresponsive and fill up memory on the host system. Version 0.17.2 patches the issue.
Which versions are affected by CVE-2026-24738?
3 open source packages ship an affected version, including github.com/gmrtd/gmrtd. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/gmrtd/gmrtd Go | All versions | 0.17.2 |
github.com/gmrtd/gmrtd Go | All versions | 0.17.2 |
github.com/gmrtd/gmrtd Go | All versions | 0.17.2 |
Products include Gmrtd Gmrtd.
How do I fix CVE-2026-24738?
Upgrade github.com/gmrtd/gmrtd to 0.17.2 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-2026-24738 being exploited?
There is no known exploitation of CVE-2026-24738 in the wild and no public exploit code.
Sources
Also known as GHSA-j49h-6577-5xwq, GO-2026-4379.