CVE-2026-40386
Description
A flaw was found in libexif. An integer underflow vulnerability in the size checking mechanism for Fuji and Olympus MakerNote decoding could allow attackers to exploit programs using libexif. This could lead to a Denial of Service (DoS) by crashing the program or result in information disclosure, potentially exposing sensitive data.
Statement
Moderate impact. An integer underflow in libexif's Fuji and Olympus MakerNote decoding could allow an attacker to cause a denial of service or information disclosure. This vulnerability affects programs that process specially crafted image files utilizing libexif.
Mitigation
To mitigate this issue, users should avoid processing untrusted image files with applications that utilize libexif. Restricting the source of image files to trusted origins can reduce the risk of exploitation.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4 | 7.1 | 4 |
| Attack Vector | Local | Local | Local |
| Attack Complexity | High | Low | High |
| Privileges Required | None | Low | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | Low | High | Low |
| Integrity Impact | None | None | None |
| Availability Impact | Low | High | Low |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
cve.org: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability
This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.
Integrity
Technical Impact: Modify Memory
If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.
Confidentiality,Availability,Access Control
Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism
This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.
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