How severe is CVE-2021-39290?

CVE-2021-39290 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-39290 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39290?

CVE-2021-39290 affects Netmodule Netmodule Router Software. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-39290?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-39290 published?

CVE-2021-39290 was published on 2021-08-23 and last updated on 2026-06-17.

CVE-2021-39290

CVE-2021-39290 is a critical-severity vulnerability in Netmodule Netmodule Router Software with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-384.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-384
Affected product: Netmodule Netmodule Router Software
Published: 2021-08-23
Last modified: 2026-06-17

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.

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.
How severe is CVE-2021-39290?: CVE-2021-39290 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-39290 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39290?: CVE-2021-39290 affects Netmodule Netmodule Router Software. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-39290?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-39290 published?: CVE-2021-39290 was published on 2021-08-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:netmodule:netmodule_router_software:*:*:*:*:*:*:*:*

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