CVE-2022-20946
CVE-2022-20946 is a high-severity vulnerability in Cisco Firepower Threat Defense 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-787.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- EPSS exploit prediction: 1% (54th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Cisco Firepower Threat Defense
- Published:
- Last modified:
Description
A vulnerability in the generic routing encapsulation (GRE) tunnel decapsulation feature of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to a memory handling error that occurs when GRE traffic is processed. An attacker could exploit this vulnerability by sending a crafted GRE payload through an affected device. A successful exploit could allow the attacker to cause the device to restart, resulting in a DoS condition. https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-gre-dos-hmedHQPM ["https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-gre-dos-hmedHQPM"] This advisory is part of the November 2022 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication.
Frequently asked questions
- What is CVE-2022-20946?
- A vulnerability in the generic routing encapsulation (GRE) tunnel decapsulation feature of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to a memory handling error that occurs when GRE traffic is processed. An attacker could exploit this vulnerability by sending a crafted GRE payload through an affected device. A successful exploit could allow the attacker to cause the device to restart, resulting in a DoS condition. https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-gre-dos-hmedHQPM ["https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-gre-dos-hmedHQPM"] This advisory is part of the November 2022 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication.
- How severe is CVE-2022-20946?
- CVE-2022-20946 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-2022-20946 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2022-20946?
- CVE-2022-20946 primarily affects Cisco Firepower Threat Defense. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2022-20946?
- 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-2022-20946 published?
- CVE-2022-20946 was published on 2022-11-15 and last updated on 2026-06-17.
References
Affected products (4)
- cpe:2.3:a:cisco:firepower_threat_defense:*:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.1.0.0:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.1.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:firepower_threat_defense:7.1.0.2:*:*:*:*:*:*:*
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