How severe is CVE-2021-31698?

CVE-2021-31698 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-2021-31698 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31698?

CVE-2021-31698 affects Quectel Eg25-g Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-31698?

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-2021-31698 published?

CVE-2021-31698 was published on 2021-08-12 and last updated on 2026-06-17.

CVE-2021-31698

CVE-2021-31698 is a critical-severity vulnerability in Quectel Eg25-g Firmware 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-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Quectel Eg25-g Firmware
Published: 2021-08-12
Last modified: 2026-06-17

Description

Quectel EG25-G devices through 202006130814 allow executing arbitrary code remotely by using an AT command to place shell metacharacters in quectel_handle_fumo_cfg input in atfwd_daemon.

Frequently asked questions

What is CVE-2021-31698?: Quectel EG25-G devices through 202006130814 allow executing arbitrary code remotely by using an AT command to place shell metacharacters in quectel_handle_fumo_cfg input in atfwd_daemon.
How severe is CVE-2021-31698?: CVE-2021-31698 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-2021-31698 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31698?: CVE-2021-31698 affects Quectel Eg25-g Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-31698?: 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-2021-31698 published?: CVE-2021-31698 was published on 2021-08-12 and last updated on 2026-06-17.

References

https://nns.ee/blog/2021/04/03/modem-rce.html

Affected products (1)

cpe:2.3:o:quectel:eg25-g_firmware:*:*:*:*:*:*:*:*

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