How severe is CVE-2023-20080?

CVE-2023-20080 has a CVSS 3.x base score of 8.6, 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-2023-20080 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-20080?

CVE-2023-20080 primarily affects Cisco Ios. In total, 852 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-20080?

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-2023-20080 published?

CVE-2023-20080 was published on 2023-03-23 and last updated on 2026-06-17.

CVE-2023-20080

CVE-2023-20080 is a high-severity vulnerability in Cisco Ios with a CVSS 3.x base score of 8.6. 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-129.

Key facts

Severity: High (CVSS 3.x base score 8.6)
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-129
Affected product: Cisco Ios
Published: 2023-03-23
Last modified: 2026-06-17

Description

A vulnerability in the IPv6 DHCP version 6 (DHCPv6) relay and server features of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to insufficient validation of data boundaries. An attacker could exploit this vulnerability by sending crafted DHCPv6 messages to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly.

Frequently asked questions

What is CVE-2023-20080?: A vulnerability in the IPv6 DHCP version 6 (DHCPv6) relay and server features of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to insufficient validation of data boundaries. An attacker could exploit this vulnerability by sending crafted DHCPv6 messages to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly.
How severe is CVE-2023-20080?: CVE-2023-20080 has a CVSS 3.x base score of 8.6, 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-2023-20080 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-20080?: CVE-2023-20080 primarily affects Cisco Ios. In total, 852 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-20080?: 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-2023-20080 published?: CVE-2023-20080 was published on 2023-03-23 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-dhcpv6-dos-44cMvdDK

Affected products (852)

cpe:2.3:o:cisco:ios:12.2\(6\)i1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sg8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy4a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy11:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy12:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy13:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy14:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy15:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy16:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(2\)sy16a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svr10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svs:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svt1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svt3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svt4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svu1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svu2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svu10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svu11:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svu20:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svu21:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.1\(3\)svv1:*:*:*:*:*:*:*

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