How severe is CVE-2026-31255?

CVE-2026-31255 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-2026-31255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-31255?

CVE-2026-31255 affects Tenda Ac18 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-31255?

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.

Does CVE-2026-31255 have an EU (EUVD) identifier?

Yes. CVE-2026-31255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25898.

When was CVE-2026-31255 published?

CVE-2026-31255 was published on 2026-04-27 and last updated on 2026-06-17.

CVE-2026-31255

CVE-2026-31255 is a critical-severity vulnerability in Tenda Ac18 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-77.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (73rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-25898
Weakness: CWE-77
Affected product: Tenda Ac18 Firmware
Published: 2026-04-27
Last modified: 2026-06-17

Description

A command injection vulnerability exists in Tenda AC18 V15.03.05.05_multi. The vulnerability is located in the /goform/SetSambaCfg interface, where improper handling of the guestuser parameter allows attackers to execute arbitrary system commands.

Frequently asked questions

What is CVE-2026-31255?: A command injection vulnerability exists in Tenda AC18 V15.03.05.05_multi. The vulnerability is located in the /goform/SetSambaCfg interface, where improper handling of the guestuser parameter allows attackers to execute arbitrary system commands.
How severe is CVE-2026-31255?: CVE-2026-31255 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-2026-31255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31255?: CVE-2026-31255 affects Tenda Ac18 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-31255?: 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.
Does CVE-2026-31255 have an EU (EUVD) identifier?: Yes. CVE-2026-31255 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25898.
When was CVE-2026-31255 published?: CVE-2026-31255 was published on 2026-04-27 and last updated on 2026-06-17.

References

https://github.com/izxnfirh8148/CVE_REQUESTS_references/blob/main/Tenda_AC18/Tenda_AC18_3th/README.md

Affected products (1)

cpe:2.3:o:tenda:ac18_firmware:15.03.05.05:*:*:*:*:*:*:*

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