How severe is CVE-2020-3226?

CVE-2020-3226 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-2020-3226 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3226?

CVE-2020-3226 primarily affects Cisco Ios. In total, 260 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-3226?

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-2020-3226 published?

CVE-2020-3226 was published on 2020-06-03 and last updated on 2026-06-17.

CVE-2020-3226

CVE-2020-3226 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.6)
CVSS v2: 7.8
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios
Published: 2020-06-03
Last modified: 2026-06-17

Description

A vulnerability in the Session Initiation Protocol (SIP) library of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient sanity checks on received SIP messages. An attacker could exploit this vulnerability by sending crafted SIP messages to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service condition.

Frequently asked questions

What is CVE-2020-3226?: A vulnerability in the Session Initiation Protocol (SIP) library of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient sanity checks on received SIP messages. An attacker could exploit this vulnerability by sending crafted SIP messages to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service condition.
How severe is CVE-2020-3226?: CVE-2020-3226 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-2020-3226 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3226?: CVE-2020-3226 primarily affects Cisco Ios. In total, 260 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-3226?: 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-2020-3226 published?: CVE-2020-3226 was published on 2020-06-03 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sip-Cv28sQw2

Affected products (260)

cpe:2.3:o:cisco:ios:15.0\(2\)sg11a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)jaa1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)jpi:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)jpj:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m8a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)m10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.3\(3\)xb12:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(1\)cg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(1\)t:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(1\)t1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(1\)t2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(1\)t3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(1\)t4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(2\)cg:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(2\)t:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(2\)t1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(2\)t2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(2\)t3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(2\)t4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m6a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m7a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:15.4\(3\)m8:*:*:*:*:*:*:*

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