How severe is CVE-2018-8826?

CVE-2018-8826 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-2018-8826 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8826?

CVE-2018-8826 primarily affects Asus Rt-ac51u Firmware. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-8826?

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-2018-8826 published?

CVE-2018-8826 was published on 2018-04-20 and last updated on 2026-06-17.

CVE-2018-8826

CVE-2018-8826 is a critical-severity vulnerability in Asus Rt-ac51u 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Asus Rt-ac51u Firmware
Published: 2018-04-20
Last modified: 2026-06-17

Description

ASUS RT-AC51U, RT-AC58U, RT-AC66U, RT-AC1750, RT-ACRH13, and RT-N12 D1 routers with firmware before 3.0.0.4.380.8228; RT-AC52U B1, RT-AC1200 and RT-N600 routers with firmware before 3.0.0.4.380.10446; RT-AC55U and RT-AC55UHP routers with firmware before 3.0.0.4.382.50276; RT-AC86U and RT-AC2900 routers with firmware before 3.0.0.4.384.20648; and possibly other RT-series routers allow remote attackers to execute arbitrary code via unspecified vectors.

Frequently asked questions

What is CVE-2018-8826?: ASUS RT-AC51U, RT-AC58U, RT-AC66U, RT-AC1750, RT-ACRH13, and RT-N12 D1 routers with firmware before 3.0.0.4.380.8228; RT-AC52U B1, RT-AC1200 and RT-N600 routers with firmware before 3.0.0.4.380.10446; RT-AC55U and RT-AC55UHP routers with firmware before 3.0.0.4.382.50276; RT-AC86U and RT-AC2900 routers with firmware before 3.0.0.4.384.20648; and possibly other RT-series routers allow remote attackers to execute arbitrary code via unspecified vectors.
How severe is CVE-2018-8826?: CVE-2018-8826 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-2018-8826 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8826?: CVE-2018-8826 primarily affects Asus Rt-ac51u Firmware. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-8826?: 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-2018-8826 published?: CVE-2018-8826 was published on 2018-04-20 and last updated on 2026-06-17.

References

Affected products (13)

cpe:2.3:o:asus:rt-ac51u_firmware:3.0.0.4.380.8228:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac58u_firmware:3.0.0.4.380.8228:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac66u_firmware:3.0.0.4.380.8228:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac1750_firmware:3.0.0.4.380.8228:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-n12_d1_firmware:3.0.0.4.380.8228:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac52u_b1_firmware:3.0.0.4.380.10446:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac1200_firmware:3.0.0.4.380.10446:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-n600_firmware:3.0.0.4.380.10446:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac55u_firmware:3.0.0.4.382.50276:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac55uhp_firmware:3.0.0.4.382.50276:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac86u_firmware:3.0.0.4.384.20648:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-acrh13_firmware:3.0.0.4.380.8228:*:*:*:*:*:*:*
cpe:2.3:o:asus:rt-ac2900_firmware:3.0.0.4.384.20648:*:*:*:*:*:*:*

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