CVE-2021-39290
CVSS v3
9.8
CRITICAL
EPSS Score
1.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Certain NetModule devices allow Limited Session Fixation via PHPSESSID. These models with firmware before 4.3.0.113, 4.4.0.111, and 4.5.0.105 are affected: NB800, NB1600, NB1601, NB1800, NB1810, NB2700, NB2710, NB2800, NB2810, NB3700, NB3701, NB3710, NB3711, NB3720, and NB3800.
Technical details
- Published
- 2021-08-23
Frequently asked questions
What is CVE-2021-39290?
Certain NetModule devices allow Limited Session Fixation via PHPSESSID. These models with firmware before 4.3.0.113, 4.4.0.111, and 4.5.0.105 are affected: NB800, NB1600, NB1601, NB1800, NB1810, NB2700, NB2710, NB2800, NB2810, NB3700, NB3701, NB3710, NB3711, NB3720, and NB3800.
Is CVE-2021-39290 actively exploited?
Active exploitation of CVE-2021-39290 has not been confirmed. Its EPSS score was 1.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-39290?
CVE-2021-39290 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-39290 affecting your environment?
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