CVE-2026-121926yezhihao jt808-server improper authentication
CVE-2026-121926 is a improper authentication in yezhihao jt808-server, rated medium (5.5 on CVSS 4.0).
Why this priority: A public proof of concept exists and exploitation can be automated.
Published · Updated · NVD status: Deferred
What it is
The software does not prove who a caller is, so an attacker can pass as someone else. A function that should require sign-in can be called by anyone.
How it is reached
An attacker can exploit it over the network, without an account, and nobody has to click anything.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker act as a signed-in user, or an administrator, without valid credentials.
Is it being exploited?
CISA's SSVC assessment notes a public proof of concept. It can be exploited automatically, at scale. EPSS estimates a 0.39% chance of exploitation activity in the next 30 days, higher than 33% of scored CVEs.
What to do
- No fixed version is listed yet. Find every place yezhihao jt808-server runs, watch the references for a fix, and plan a replacement if it is no longer supported.
- While there is no fix, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
Description from NVD
A vulnerability was detected in yezhihao jt808-server up to a07f68c466b560b97ef41edb8a4966469abdf83e. Affected is the function WebMvcConfig.addInterceptors of the component Web Management API. The manipulation results in missing authentication. The attack may be launched remotely. The exploit is now public and may be used. This product operates on a rolling release basis, ensuring continuous delivery. Consequently, there are no version details for either affected or updated releases. The vendor was contacted early about this disclosure but did not respond in any way.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Sign-in, session and token handling. The flaw sits between anonymous callers and authenticated sessions.
- Identity providers and SSO. The flaw sits between anonymous callers and authenticated sessions.
Trust boundaries in play
- Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
- Between anonymous callers and authenticated sessions. An attacker who crosses it can act as a signed-in user, or an administrator, without valid credentials.
Questions to answer about your own systems
- Where does yezhihao jt808-server run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.