CVE-2022-20826

A vulnerability in the secure boot implementation of Cisco Secure Firewalls 3100 Series that are running Cisco Adaptive Security Appliance (ASA) Software or Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated attacker with physical access to the device to bypass the secure boot functionality. This vulnerability is due to a logic error in the boot process. An attacker could exploit this vulnerability by injecting malicious code into a specific memory location during the boot process of an affected device. A successful exploit could allow the attacker to execute persistent code at boot time and break the chain of trust.

Published: 2022-11-15 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2022-20826 is rated Moderate Risk (46.8/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.40%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-20826

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-10 0.29% 0.40% +0.11%
2 2025-11-23 0.09% 0.29% +0.21%
3 2025-11-17 — 0.09% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-20826

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.4 3.1 MEDIUM
CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:P)
Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 0.5 5.9 [email protected]
6.8 3.1 MEDIUM
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:P)
Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 0.9 5.9 [email protected]

Weakness enumeration for CVE-2022-20826

Affected software / configurations for CVE-2022-20826

Vendor Product Version Raw CPE
cisco adaptive_security_appliance_software 9.17.1 cpe:2.3:o:cisco:adaptive_security_appliance_software:9.17.1:*:*:*:*:*:*:*
cisco adaptive_security_appliance_software 9.17.1.9 cpe:2.3:o:cisco:adaptive_security_appliance_software:9.17.1.9:*:*:*:*:*:*:*
cisco adaptive_security_appliance_software 9.17.1.10 cpe:2.3:o:cisco:adaptive_security_appliance_software:9.17.1.10:*:*:*:*:*:*:*
cisco adaptive_security_appliance_software 9.17.1.13 cpe:2.3:o:cisco:adaptive_security_appliance_software:9.17.1.13:*:*:*:*:*:*:*
cisco adaptive_security_appliance_software 9.18.1 cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.1:*:*:*:*:*:*:*
cisco adaptive_security_appliance_software 9.18.1.3 cpe:2.3:o:cisco:adaptive_security_appliance_software:9.18.1.3:*:*:*:*:*:*:*
cisco firepower_threat_defense 7.1.0.0 cpe:2.3:a:cisco:firepower_threat_defense:7.1.0.0:*:*:*:*:*:*:*
cisco firepower_threat_defense 7.2.0.0 cpe:2.3:a:cisco:firepower_threat_defense:7.2.0.0:*:*:*:*:*:*:*
cisco firepower_threat_defense 7.2.0.1 cpe:2.3:a:cisco:firepower_threat_defense:7.2.0.1:*:*:*:*:*:*:*

References for CVE-2022-20826

cvelogic Threat Intelligence