How severe is CVE-2020-9276?

CVE-2020-9276 has a CVSS 3.x base score of 8.8, rated high 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-2020-9276 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-9276?

CVE-2020-9276 affects Dlink Dsl-2640b Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-9276?

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-2020-9276 published?

CVE-2020-9276 was published on 2020-04-20 and last updated on 2026-06-17.

CVE-2020-9276

CVE-2020-9276 is a high-severity vulnerability in Dlink Dsl-2640b Firmware with a CVSS 3.x base score of 8.8. 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Dlink Dsl-2640b Firmware
Published: 2020-04-20
Last modified: 2026-06-17

Description

An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. The function do_cgi(), which processes cgi requests supplied to the device's web servers, is vulnerable to a remotely exploitable stack-based buffer overflow. Unauthenticated exploitation is possible by combining this vulnerability with CVE-2020-9277.

Frequently asked questions

What is CVE-2020-9276?: An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. The function do_cgi(), which processes cgi requests supplied to the device's web servers, is vulnerable to a remotely exploitable stack-based buffer overflow. Unauthenticated exploitation is possible by combining this vulnerability with CVE-2020-9277.
How severe is CVE-2020-9276?: CVE-2020-9276 has a CVSS 3.x base score of 8.8, rated high 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-2020-9276 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-9276?: CVE-2020-9276 affects Dlink Dsl-2640b Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-9276?: 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-2020-9276 published?: CVE-2020-9276 was published on 2020-04-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dsl-2640b_firmware:eu_4.01b:*:*:*:*:*:*:*

More vulnerabilities in Dlink Dsl-2640b Firmware

CVE-2020-9279 — Critical (CVSS 9.8): An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. A hard-coded account allows management-interface login…
CVE-2020-9277 — Critical (CVSS 9.8): An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. Authentication can be bypassed when accessing cgi…
CVE-2020-9275 — Critical (CVSS 9.8): An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. A cfm UDP service listening on port 65002 allows…
CVE-2020-9278 — Critical (CVSS 9.1): An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. The device can be reset to its default configuration…
CVE-2012-1308 — Medium (CVSS 6.8): Cross-site request forgery (CSRF) vulnerability in redpass.cgi in D-Link DSL-2640B Firmware EU_4.00 allows remote…

All CVEs affecting Dlink Dsl-2640b Firmware →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src‎ modules). This vulnerability is…
CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →