What is CVE-2026-20049?

CVE-2026-20049 is a high-severity vulnerability in Cisco Secure Firewall Adaptive Security Appliance (Asa) Software, classified under Incorrect Calculation of Buffer Size. CVSS score: 7.7/10. Published 2026-03-04.

How severe is CVE-2026-20049?

High severity. CVSS v3 base score is 7.7 out of 10.

Vulnerability in Cisco Secure Firewall Adaptive Security Appliance (Asa) Software

CVE-2026-20049

A vulnerability in the processing of Galois/Counter Mode (GCM)-encrypted Internet Key Exchange version 2 (IKEv2) IPsec traffic of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FT…

EPSS: 0.002 (42.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.

Affected products

Cisco Secure Firewall Adaptive Security Appliance (Asa) Software — versions 9.12.4.7, 9.12.4.10, 9.12.4.13
Cisco Secure Firewall Threat Defense (Ftd) Software — versions 6.4.0.10, 6.4.0.11, 6.4.0.12

Weakness classification (CWE)

CWE-131 — Incorrect Calculation of Buffer Size

References

cisco-sa-asaftd-esp-dos-uv7yD8P5

Frequently asked questions

What is CVE-2026-20049?: CVE-2026-20049 is a high-severity vulnerability in Cisco Secure Firewall Adaptive Security Appliance (Asa) Software, classified under Incorrect Calculation of Buffer Size. CVSS score: 7.7/10. Published 2026-03-04.
How severe is CVE-2026-20049?: High severity. CVSS v3 base score is 7.7 out of 10.