How severe is CVE-2020-9544?

CVE-2020-9544 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2020-9544 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-9544?

CVE-2020-9544 affects D-link Dsl-2640b Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-9544?

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

When was CVE-2020-9544 published?

CVE-2020-9544 was published on 2020-03-05 and last updated on 2026-06-17.

CVE-2020-9544

CVE-2020-9544 is a high-severity vulnerability in D-link Dsl-2640b Firmware with a CVSS 3.x base score of 7.5. 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-306.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: D-link Dsl-2640b Firmware
Published: 2020-03-05
Last modified: 2026-06-17

Description

An issue was discovered on D-Link DSL-2640B E1 EU_1.01 devices. The administrative interface doesn't perform authentication checks for a firmware-update POST request. Any attacker that can access the administrative interface can install firmware of their choice.

Frequently asked questions

What is CVE-2020-9544?: An issue was discovered on D-Link DSL-2640B E1 EU_1.01 devices. The administrative interface doesn't perform authentication checks for a firmware-update POST request. Any attacker that can access the administrative interface can install firmware of their choice.
How severe is CVE-2020-9544?: CVE-2020-9544 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2020-9544 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-9544?: CVE-2020-9544 affects D-link Dsl-2640b Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-9544?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-9544 published?: CVE-2020-9544 was published on 2020-03-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:d-link:dsl-2640b_firmware:e1_eu_1.01:*:*:*:*:*:*:*

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