How severe is CVE-2026-20050?

CVE-2026-20050 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-20050 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-20050?

CVE-2026-20050 affects Cisco Secure Firewall Threat Defense. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-20050?

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

Does CVE-2026-20050 have an EU (EUVD) identifier?

Yes. CVE-2026-20050 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9457.

When was CVE-2026-20050 published?

CVE-2026-20050 was published on 2026-03-04 and last updated on 2026-08-11.

CVE-2026-20050

CVE-2026-20050 is a medium-severity vulnerability in Cisco Secure Firewall Threat Defense with a CVSS 3.x base score of 6.8. 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-404.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-9457
Weakness: CWE-404
Affected product: Cisco Secure Firewall Threat Defense
Published: 2026-03-04
Last modified: 2026-08-11

Description

A vulnerability in the Do Not Decrypt exclusion feature of the SSL decryption feature of Cisco Secure Firewall 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 improper memory management during the inspection of TLS 1.2 encrypted traffic. An attacker could exploit this vulnerability by sending crafted TLS 1.2 encrypted traffic through an affected device. A successful exploit could allow the attacker to cause a reload of an affected device. Note: This vulnerability only affects traffic that is encrypted by TLS 1.2. Other versions of TLS are not affected.

Frequently asked questions

What is CVE-2026-20050?: A vulnerability in the Do Not Decrypt exclusion feature of the SSL decryption feature of Cisco Secure Firewall 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 improper memory management during the inspection of TLS 1.2 encrypted traffic. An attacker could exploit this vulnerability by sending crafted TLS 1.2 encrypted traffic through an affected device. A successful exploit could allow the attacker to cause a reload of an affected device. Note: This vulnerability only affects traffic that is encrypted by TLS 1.2. Other versions of TLS are not affected.
How severe is CVE-2026-20050?: CVE-2026-20050 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-20050 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-20050?: CVE-2026-20050 affects Cisco Secure Firewall Threat Defense. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-20050?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-20050 have an EU (EUVD) identifier?: Yes. CVE-2026-20050 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9457.
When was CVE-2026-20050 published?: CVE-2026-20050 was published on 2026-03-04 and last updated on 2026-08-11.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-dnd-dos-bpEcg7B7

Affected products (1)

cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*

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