Cyber Resilience

CVE-2021-39243

MediumPublic PoC

Published: 23 August 2021

Published
23 August 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
EPSS Score 0.0016 37.3th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-39243 is a medium-severity CSRF (CWE-352) vulnerability in Altus Nexto Nx3003 Firmware. Its CVSS base score is 6.5 (Medium).

Operationally, ranked at the 37.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Cross-Site Request Forgery (CSRF) exists on Altus Nexto, Nexto Xpress, and Hadron Xtorm devices via any CGI endpoint. This affects Nexto NX3003 1.8.11.0, Nexto NX3004 1.8.11.0, Nexto NX3005 1.8.11.0, Nexto NX3010 1.8.3.0, Nexto NX3020 1.8.3.0, Nexto NX3030 1.8.3.0, Nexto NX5100…

more

1.8.11.0, Nexto NX5101 1.8.11.0, Nexto NX5110 1.1.2.8, Nexto NX5210 1.1.2.8, Nexto Xpress XP300 1.8.11.0, Nexto Xpress XP315 1.8.11.0, Nexto Xpress XP325 1.8.11.0, Nexto Xpress XP340 1.8.11.0, and Hadron Xtorm HX3040 1.7.58.0.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

altus
nexto nx3003 firmware
1.8.11.0
altus
nexto nx3004 firmware
1.8.11.0
altus
nexto nx3005 firmware
1.8.11.0
altus
nexto nx3010 firmware
1.8.3.0
altus
nexto nx3020 firmware
1.8.3.0
altus
nexto nx3030 firmware
1.8.3.0
altus
nexto nx5100 firmware
1.8.11.0
altus
nexto nx5101 firmware
1.8.11.0
altus
nexto nx5110 firmware
1.1.2.8
altus
nexto nx5210 firmware
1.1.2.8
+5 more product configuration(s) — see NVD for full list

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-352

Awareness training educates users on avoiding untrusted links and actions that can be exploited via CSRF.

addresses: CWE-352

Requiring user re-entry of credentials for sensitive actions prevents automated forgery of requests without active user participation.

addresses: CWE-352

Security testing regimens explicitly include checks for missing or ineffective anti-CSRF protections in web applications.

addresses: CWE-352

Detects anomalous request patterns consistent with cross-site request forgery.

References