5.5

CVE-2023-40550: fedoraproject fedora Out-of-bounds Read

CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2023-40550DEBIAN-CVE-2023-40550
Published 29-01-2024Last modified 27-01-2026
Open JSON

Vulnerability summary

CVE-2023-40550 is a medium (CVSS 5.5) Out-of-bounds Read vulnerability in fedoraproject fedora. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 32.4% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.40%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 14 · Related 4
DLA-3813-1RHSA-2024:1834RHSA-2024:1835RHSA-2024:1873RHSA-2024:1876RHSA-2024:1883

Timeline

  1. 29-01-2024
    PublishedVulnerability first disclosed.
  2. 27-01-2026
    Last modifiedVulnerability information updated.

Description

An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.40%

Chance of exploitation in the next 30 days

Percentile

32%

Versus all other CVEs

30-day change

0.00 pp

From 0.40% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.40%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Redhat2 products
Ubuntu2 products
  • shimAll versions (No fix recorded) | < 15.8-0ubuntu1
  • shim-signedAll versions (No fix recorded) | < 1.40.10 | < 1.51.4 | < 1.58
Debian1 product
  • shim< 15.8-1~deb12u1 | < 15.8-1
Fedoraproject1 product

4 vendors · 6 products

References

16 links
Show all 16 references