Quick answers
- Is CVE-2026-17251 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-17251 being exploited in the wild.
- How severe is CVE-2026-17251?
- Informational severity, with a CVSS score of 5.3, published 21 August 2026.
- Which products and versions are affected?
- TP-Link TL-MR6400 v7.
- Is there a fix for CVE-2026-17251?
- A patch was published on 2026-08-19: Firmware build 260714 released with security improvements Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-17251 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-17251?
- Check whether you run TP-Link TL-MR6400 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.
Technical details
A NULL pointer dereference vulnerability exists in the HTTP request parsing functionality of TL-MR6400 v7. The vulnerability can be triggered by an unauthenticated remote attacker sending a specially crafted HTTP request with a malformed session cookie header. The flaw causes a crash of the HTTP service process, leading to a denial-of-service condition. The vulnerability is network-reachable and requires no prior authentication or user interaction. Exploitation results in temporary unavailability of management and CGI services until the router process recovers.
Affected products
- TP-Link TL-MR6400 v7
Timeline
- 2026-08-21: disclosed
- 2026-08-19: patched: Firmware build 260714 released with security improvements