How severe is CVE-2021-29294?

CVE-2021-29294 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 none, and availability high.

Is CVE-2021-29294 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29294?

CVE-2021-29294 affects Dlink Dsl-2740r Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29294?

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-2021-29294 published?

CVE-2021-29294 was published on 2021-08-10 and last updated on 2026-06-17.

CVE-2021-29294

CVE-2021-29294 is a high-severity vulnerability in Dlink Dsl-2740r 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Dlink Dsl-2740r Firmware
Published: 2021-08-10
Last modified: 2026-06-17

Description

Null Pointer Dereference vulnerability exists in D-Link DSL-2740R UK_1.01, which could let a remove malicious user cause a denial of service via the send_hnap_unauthorized function. It could be triggered by sending crafted POST request to /HNAP1/. NOTE: The DSL-2740R and all hardware revisions are considered End of Life and as such this issue will not be patched

Frequently asked questions

What is CVE-2021-29294?: Null Pointer Dereference vulnerability exists in D-Link DSL-2740R UK_1.01, which could let a remove malicious user cause a denial of service via the send_hnap_unauthorized function. It could be triggered by sending crafted POST request to /HNAP1/. NOTE: The DSL-2740R and all hardware revisions are considered End of Life and as such this issue will not be patched
How severe is CVE-2021-29294?: CVE-2021-29294 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 none, and availability high.
Is CVE-2021-29294 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29294?: CVE-2021-29294 affects Dlink Dsl-2740r Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29294?: 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-2021-29294 published?: CVE-2021-29294 was published on 2021-08-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dsl-2740r_firmware:uk_1.01:*:*:*:*:*:*:*

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