CVE-2023-40548: fedoraproject fedora Integer Overflow or Wraparound
Vulnerability summary
CVE-2023-40548 is a high (CVSS 7.4) Integer Overflow or Wraparound vulnerability in fedoraproject fedora. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 14 · Related 4Timeline
- 29-01-2024PublishedVulnerability first disclosed.
- 26-06-2026Last modifiedVulnerability information updated.
Description
A buffer overflow was found in Shim in the 32-bit system. The overflow happens due to an addition operation involving a user-controlled value parsed from the PE binary being used by Shim. This value is further used for memory allocation operations, leading to a heap-based buffer overflow. This flaw causes memory corruption and can lead to a crash or data integrity issues during the boot phase.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.4HighCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.4HighCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST7.4HighCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.44%
Chance of exploitation in the next 30 days
Percentile
36%
Versus all other CVEs
30-day change
0.00 pp
From 0.44% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
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
- fedoraEOL39
Redhat1 product
- shim< 15.8 | 15.8:rc1
4 vendors · 5 products
