How severe is CVE-2026-77683?

CVE-2026-77683 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-77683 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-77683?

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-2026-77683 published?

CVE-2026-77683 was published on 2026-08-21.

CVE-2026-77683

CVE-2026-77683 is a critical-severity vulnerability with a CVSS 3.x base score of 9.9. 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-74.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
CVSS v2: 9.0
CVSS v4: 8.6
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Published: 2026-08-21
Last modified: 2026-08-21

Description

A security flaw has been discovered in Comfast CF-N1-S 2.6.0.1. Affected by this issue is the function system of the file /cgi-bin/mbox-config?method=SET&section=ntp_timezone. The manipulation of the argument timestr results in command injection. The attack can be launched remotely. The exploit has been released to the public and may be used for attacks.

Frequently asked questions

What is CVE-2026-77683?: A security flaw has been discovered in Comfast CF-N1-S 2.6.0.1. Affected by this issue is the function system of the file /cgi-bin/mbox-config?method=SET&section=ntp_timezone. The manipulation of the argument timestr results in command injection. The attack can be launched remotely. The exploit has been released to the public and may be used for attacks.
How severe is CVE-2026-77683?: CVE-2026-77683 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-77683 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-77683?: 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-2026-77683 published?: CVE-2026-77683 was published on 2026-08-21.

References

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