CVE-2026-26305
Published: 27 February 2026
Summary
CVE-2026-26305 is a high-severity Improper Restriction of Excessive Authentication Attempts (CWE-307) vulnerability in Mobility46 Mobility46.Se. Its CVSS base score is 8.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked at the 37.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-7 (Unsuccessful Logon Attempts) and SC-5 (Denial-of-service Protection).
Deeper analysis
CVE-2026-26305 is a vulnerability in the WebSocket Application Programming Interface that lacks restrictions on the number of authentication requests due to the absence of rate limiting. This issue, tied to CWE-307 (Improper Restriction of Excessive Authentication Attempts), carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) and was published on 2026-02-27T01:16:20.617. It affects systems handling charger telemetry, as detailed in the associated CISA ICS advisory.
A remote attacker requires no privileges or user interaction and can exploit this over the network with low complexity. Successful exploitation enables denial-of-service attacks by suppressing or mis-routing legitimate charger telemetry, or brute-force attacks to achieve unauthorized access.
CISA advisory ICSA-26-057-08 provides details on the vulnerability, available at https://www.cisa.gov/news-events/ics-advisories/icsa-26-057-08 and the corresponding CSAF JSON at https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-057-08.json. Vendor contact information is at https://www.mobility46.se/en/contact-us.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8962
Vulnerability details
The WebSocket Application Programming Interface lacks restrictions on the number of authentication requests. This absence of rate limiting may allow an attacker to conduct denial-of-service attacks by suppressing or mis-routing legitimate charger telemetry, or conduct brute-force attacks to gain unauthorized…
more
access.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Lack of rate limiting on public-facing WebSocket auth API directly enables brute force credential attacks (T1110) and application-layer DoS via request flooding (T1499); exploitation occurs remotely against exposed service (T1190).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly enforces limits on consecutive invalid authentication attempts, preventing brute-force attacks and DoS from excessive WebSocket authentication requests.
Provides denial-of-service protection mechanisms to limit the effects of excessive authentication requests that suppress or mis-route legitimate charger telemetry.
Ensures resource availability by prioritizing and managing allocations, mitigating resource exhaustion from floods of authentication requests.