Quick answers
- Is CVE-2026-76856 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-76856 being exploited in the wild.
- How severe is CVE-2026-76856?
- High severity, with a CVSS score of 8.1, published 15 September 2026.
- Which products and versions are affected?
- Netcore NR255-V 1.5.130703.
- Is there a fix for CVE-2026-76856?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-76856 attacked?
- It is attacked over the network, in device firmware.
- Am I affected by CVE-2026-76856?
- Check whether you run Netcore NR255-V 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
The Netcore NR255-V firmware 1.5.130703 contains a cross-site request forgery (CSRF) vulnerability in the wan_config_set_cgi, wan_num_set_cgi, and lan_ip_change_cgi endpoints. These endpoints lack proper CSRF protection (such as anti-CSRF tokens), allowing attackers to craft forged HTTP requests that execute with the privileges of an authenticated administrator. The attack requires that an administrator be logged into the router's web interface and be tricked into visiting a malicious webpage controlled by the attacker. A successful exploit enables unauthorized modification of WAN and LAN configuration settings, potentially disrupting network connectivity or redirecting traffic. Netcore has not released a patch as of the advisory date.
Affected products
- Netcore NR255-V 1.5.130703
Timeline
- 2026-09-15: disclosed: CVE-2026-76856 published on NVD
- 2026-09-04: other: Public reference published on GitHub by researchers Zhou Ao, Yin Luxing, Jiang Yuxuan, Liu Xin, @Nebusec