How severe is CVE-2024-20451?

CVE-2024-20451 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-2024-20451 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-20451?

CVE-2024-20451 primarily affects Cisco Spa 301 Firmware. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-20451?

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.

Does CVE-2024-20451 have an EU (EUVD) identifier?

Yes. CVE-2024-20451 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18166.

When was CVE-2024-20451 published?

CVE-2024-20451 was published on 2024-08-07 and last updated on 2026-06-17.

CVE-2024-20451

CVE-2024-20451 is a high-severity vulnerability in Cisco Spa 301 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-120.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-18166
Weakness: CWE-120
Affected product: Cisco Spa 301 Firmware
Published: 2024-08-07
Last modified: 2026-06-17

Description

Multiple vulnerabilities in the web-based management interface of Cisco Small Business SPA300 Series IP Phones and Cisco Small Business SPA500 Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly. These vulnerabilities exist because HTTP packets are not properly checked for errors. An attacker could exploit this vulnerability by sending a crafted HTTP packet to the remote interface of an affected device. A successful exploit could allow the attacker to cause a DoS condition on the device.

Frequently asked questions

What is CVE-2024-20451?: Multiple vulnerabilities in the web-based management interface of Cisco Small Business SPA300 Series IP Phones and Cisco Small Business SPA500 Series IP Phones could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly. These vulnerabilities exist because HTTP packets are not properly checked for errors. An attacker could exploit this vulnerability by sending a crafted HTTP packet to the remote interface of an affected device. A successful exploit could allow the attacker to cause a DoS condition on the device.
How severe is CVE-2024-20451?: CVE-2024-20451 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-2024-20451 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-20451?: CVE-2024-20451 primarily affects Cisco Spa 301 Firmware. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-20451?: 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.
Does CVE-2024-20451 have an EU (EUVD) identifier?: Yes. CVE-2024-20451 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18166.
When was CVE-2024-20451 published?: CVE-2024-20451 was published on 2024-08-07 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-spa-http-vulns-RJZmX2Xz

Affected products (11)

cpe:2.3:o:cisco:spa_301_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_303_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_501g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_502g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_504g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_508g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_509g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_512g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_514g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_525g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:spa_525g2_firmware:*:*:*:*:*:*:*:*

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