How severe is CVE-2021-1614?

CVE-2021-1614 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-1614 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1614?

CVE-2021-1614 affects Cisco Sd-wan. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1614?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-1614 published?

CVE-2021-1614 was published on 2021-07-22 and last updated on 2026-06-17.

CVE-2021-1614

CVE-2021-1614 is a medium-severity vulnerability in Cisco Sd-wan with a CVSS 3.x base score of 5.3. 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-126.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-126
Affected product: Cisco Sd-wan
Published: 2021-07-22
Last modified: 2026-06-17

Description

A vulnerability in the Multiprotocol Label Switching (MPLS) packet handling function of Cisco SD-WAN Software could allow an unauthenticated, remote attacker to gain access to information stored in MPLS buffer memory. This vulnerability is due to insufficient handling of malformed MPLS packets that are processed by a device that is running Cisco SD-WAN Software. An attacker could exploit this vulnerability by sending a crafted MPLS packet to an affected device that is running Cisco SD-WAN Software or Cisco SD-WAN vManage Software. A successful exploit could allow the attacker to gain unauthorized access to sensitive information.

Frequently asked questions

What is CVE-2021-1614?: A vulnerability in the Multiprotocol Label Switching (MPLS) packet handling function of Cisco SD-WAN Software could allow an unauthenticated, remote attacker to gain access to information stored in MPLS buffer memory. This vulnerability is due to insufficient handling of malformed MPLS packets that are processed by a device that is running Cisco SD-WAN Software. An attacker could exploit this vulnerability by sending a crafted MPLS packet to an affected device that is running Cisco SD-WAN Software or Cisco SD-WAN vManage Software. A successful exploit could allow the attacker to gain unauthorized access to sensitive information.
How severe is CVE-2021-1614?: CVE-2021-1614 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-1614 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1614?: CVE-2021-1614 affects Cisco Sd-wan. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1614?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1614 published?: CVE-2021-1614 was published on 2021-07-22 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdw-mpls-infodisclos-MSSRFkZq

Affected products (1)

cpe:2.3:a:cisco:sd-wan:*:*:*:*:*:*:*:*

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