Vulnerability · Published Nov 1, 2026 · Assigned by VulDB

CVE-2026-120241Ruijie RG-ES205GC Local Firmware Upgrade httpupg.cgi buffer overflow

High 7.5

In plain English

A high-severity buffer overflow in RG-ES205GC from Ruijie. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.6%top 50.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

A vulnerability was identified in Ruijie RG-ES205GC, RG-ES206GC-P, RG-ES208GC, RG-ES210GC-LP and RG-ES210GS-P ESW_1.0(1)B1P48. Impacted is an unknown function of the file httpupg.cgi of the component Local Firmware Upgrade Interface. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Affected products (as reported)

Vendor	Product	Versions
Ruijie	RG-ES205GC	ESW_1.0(1)B1P48
Ruijie	RG-ES206GC-P	ESW_1.0(1)B1P48
Ruijie	RG-ES208GC	ESW_1.0(1)B1P48
Ruijie	RG-ES210GC-LP	ESW_1.0(1)B1P48
Ruijie	RG-ES210GS-P	ESW_1.0(1)B1P48

Weakness: CWE-120, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:R

References

VDB-429600 | Ruijie RG-ES205GC Local Firmware Upgrade httpupg.cgi buffer overflow vdb-entry
VDB-429600 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
CVE-2026-120241 | CVE Analysis and Report third-party-advisory
Submit #1016041 | Ruijie Networks Co., Ltd. RG-ES205GC, RG-ES206GC-P, RG-ES208GC, RG-ES210GC-LP, RG-ES210GS-P (sharing the same ESW firmware; NIS2100 series may also be aff ESW_1.0(1)B1P48, Release(12211919) Buffer Overflow third-party-advisory
https://github.com/byseeker/Ruijie-RG-ES-Series-Switches_PreAuth_Boundary_Overflow_DoS exploit