CVE-2026-40386: CWE-191 Integer Underflow (Wrap or Wraparound) in libexif project libexif
In libexif through 0.6.25, an integer underflow in size checking for Fuji and Olympus MakerNote decoding could be used by attackers to crash or leak information out of libexif-using programs.
AI Analysis
Technical Summary
An integer underflow (CWE-191) exists in libexif through version 0.6.25 in the size checking logic for Fuji and Olympus MakerNote decoding. This underflow can lead to improper memory handling, potentially causing application crashes or information leakage in software that utilizes libexif for image metadata processing. The vulnerability is local attack vector with high attack complexity and no privileges or user interaction required, resulting in limited confidentiality and availability impact.
Potential Impact
The vulnerability can cause denial of service (application crash) or limited information disclosure in applications using libexif for Fuji and Olympus MakerNote metadata processing. The impact is limited to confidentiality and availability with no integrity impact. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should consider limiting exposure to untrusted image files containing Fuji or Olympus MakerNote data and apply general security best practices for handling untrusted input.
CVE-2026-40386: CWE-191 Integer Underflow (Wrap or Wraparound) in libexif project libexif
Description
In libexif through 0.6.25, an integer underflow in size checking for Fuji and Olympus MakerNote decoding could be used by attackers to crash or leak information out of libexif-using programs.
CVSS v3.1
Score 4.0medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An integer underflow (CWE-191) exists in libexif through version 0.6.25 in the size checking logic for Fuji and Olympus MakerNote decoding. This underflow can lead to improper memory handling, potentially causing application crashes or information leakage in software that utilizes libexif for image metadata processing. The vulnerability is local attack vector with high attack complexity and no privileges or user interaction required, resulting in limited confidentiality and availability impact.
Potential Impact
The vulnerability can cause denial of service (application crash) or limited information disclosure in applications using libexif for Fuji and Olympus MakerNote metadata processing. The impact is limited to confidentiality and availability with no integrity impact. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should consider limiting exposure to untrusted image files containing Fuji or Olympus MakerNote data and apply general security best practices for handling untrusted input.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-04-12T18:19:08.139Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69dbe51682d89c981fa14164
Added to database: 4/12/2026, 6:31:50 PM
Last enriched: 4/20/2026, 6:05:58 AM
Last updated: 5/27/2026, 5:55:20 PM
Views: 110
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.