CVE-2026-103679: Use After Free
A flaw was found in tnef. A remote attacker could exploit this vulnerability by providing a specially crafted Transport Neutral Encapsulation Format (TNEF) file containing multiple message bodies. During extraction, improper memory management triggers a use-after-free and double-free condition, causing the application to crash and resulting in a Denial of Service (DoS).
AI Analysis
Technical Summary
The vulnerability in tnef arises from improper handling of multiple message bodies in a crafted Transport Neutral Encapsulation Format (TNEF) file. This triggers use-after-free and double-free memory errors during extraction, causing the application to crash and resulting in denial of service. The issue affects versions >=0 and <=1.4.18. There is no indication of confidentiality or integrity impact, only availability is affected. No exploits are currently known in the wild. The vendor advisory from Red Hat is available but does not specify patch status or remediation details.
Potential Impact
Successful exploitation causes application crashes leading to denial of service. There is no impact on confidentiality or integrity. The vulnerability can be triggered remotely without privileges, but requires user interaction (UI:R).
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory at https://access.redhat.com/security/cve/CVE-2026-103679 for current remediation guidance. Until a patch is applied, avoid processing untrusted TNEF files containing multiple message bodies to mitigate risk.
CVE-2026-103679: Use After Free
Description
A flaw was found in tnef. A remote attacker could exploit this vulnerability by providing a specially crafted Transport Neutral Encapsulation Format (TNEF) file containing multiple message bodies. During extraction, improper memory management triggers a use-after-free and double-free condition, causing the application to crash and resulting in a Denial of Service (DoS).
CVSS v3.1
Score 6.5medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in tnef arises from improper handling of multiple message bodies in a crafted Transport Neutral Encapsulation Format (TNEF) file. This triggers use-after-free and double-free memory errors during extraction, causing the application to crash and resulting in denial of service. The issue affects versions >=0 and <=1.4.18. There is no indication of confidentiality or integrity impact, only availability is affected. No exploits are currently known in the wild. The vendor advisory from Red Hat is available but does not specify patch status or remediation details.
Potential Impact
Successful exploitation causes application crashes leading to denial of service. There is no impact on confidentiality or integrity. The vulnerability can be triggered remotely without privileges, but requires user interaction (UI:R).
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory at https://access.redhat.com/security/cve/CVE-2026-103679 for current remediation guidance. Until a patch is applied, avoid processing untrusted TNEF files containing multiple message bodies to mitigate risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- fedora
- Date Reserved
- 2026-10-01T09:06:43.923Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-103679","vendor":"Red Hat"}]
Threat ID: 6abe7490a43b0b3b89bd1cc1
Added to database: 10/01/2026, 14:56:16 UTC
Last enriched: 10/01/2026, 15:20:38 UTC
Last updated: 10/01/2026, 23:12:14 UTC
Views: 6
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