CVE-2023-5342 | Shim: expired secure boot certificate

The Fedora Secure Boot CA certificate shipped with shim in Fedora was expired which could lead to old or invalid signed boot components being loaded.

Published: 2025-08-14 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-5342 is rated Low Risk (16.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.08%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

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-2023-5342

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 2026-06-15 0.01% 0.08% +0.07%
2 2025-08-16 — 0.01% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-5342

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.1 3.1 MEDIUM
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 0.5 3.6 [email protected]

Weakness enumeration for CVE-2023-5342

OS Trackers for CVE-2023-5342

vendor priority summary link
redhat low — https://access.redhat.com/security/cve/CVE-2023-5342

Affected software / configurations for CVE-2023-5342

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2023-5342

cvelogic Threat Intelligence