How severe is CVE-2021-1509?

CVE-2021-1509 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1509 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1509?

CVE-2021-1509 primarily affects Cisco Vedge 100 Firmware. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1509?

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-2021-1509 published?

CVE-2021-1509 was published on 2021-05-06 and last updated on 2026-06-17.

CVE-2021-1509

CVE-2021-1509 is a high-severity vulnerability in Cisco Vedge 100 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-119.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 8.5
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Cisco Vedge 100 Firmware
Published: 2021-05-06
Last modified: 2026-06-17

Description

Multiple vulnerabilities in Cisco SD-WAN vEdge Software could allow an attacker to execute arbitrary code as the root user or cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Frequently asked questions

What is CVE-2021-1509?: Multiple vulnerabilities in Cisco SD-WAN vEdge Software could allow an attacker to execute arbitrary code as the root user or cause a denial of service (DoS) condition on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.
How severe is CVE-2021-1509?: CVE-2021-1509 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1509 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1509?: CVE-2021-1509 primarily affects Cisco Vedge 100 Firmware. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1509?: 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-2021-1509 published?: CVE-2021-1509 was published on 2021-05-06 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-buffover-MWGucjtO

Affected products (16)

cpe:2.3:o:cisco:vedge_100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_1000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_1000_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100b_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100m_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100m_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100wm_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_100wm_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_2000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_2000_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_5000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_5000_firmware:19.2.99:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_cloud_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:vedge_cloud_firmware:19.2.99:*:*:*:*:*:*:*

More vulnerabilities in Cisco Vedge 100 Firmware

CVE-2019-1650 — High (CVSS 8.8): A vulnerability in the Cisco SD-WAN Solution could allow an authenticated, remote attacker to overwrite arbitrary files…
CVE-2018-0432 — High (CVSS 8.8): A vulnerability in the error reporting feature of the Cisco SD-WAN Solution could allow an authenticated, remote…
CVE-2021-1528 — High (CVSS 7.8): A vulnerability in the CLI of Cisco SD-WAN Software could allow an authenticated, local attacker to gain elevated…
CVE-2021-1514 — High (CVSS 7.8): A vulnerability in the CLI of Cisco SD-WAN Software could allow an authenticated, local attacker to inject arbitrary…
CVE-2019-1648 — High (CVSS 7.8): A vulnerability in the user group configuration of the Cisco SD-WAN Solution could allow an authenticated, local…
CVE-2019-1646 — High (CVSS 7.8): A vulnerability in the local CLI of the Cisco SD-WAN Solution could allow an authenticated, local attacker to escalate…

All CVEs affecting Cisco Vedge 100 Firmware →

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…
CVE-2025-1866 — Critical (CVSS 10.0): Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows…
CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.

Browse all CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities →