CVE-2026-34873: n/a
A vulnerability in Mbed TLS versions 3. 5. 0 through 4. 0. 0 allows client impersonation during the resumption of a TLS 1. 3 session. This security flaw can be exploited remotely without authentication or user interaction, leading to a critical impact on confidentiality and integrity. The vulnerability is identified as CWE-287, indicating improper authentication. No official patch or remediation details are provided in the current data. There are no known exploits in the wild at this time.
AI Analysis
Technical Summary
CVE-2026-34873 is a critical vulnerability in Mbed TLS versions 3.5.0 through 4.0.0 that permits client impersonation during TLS 1.3 session resumption. The flaw relates to improper authentication (CWE-287), allowing an unauthenticated remote attacker to impersonate a client, compromising confidentiality and integrity of the TLS session. The CVSS v3.1 base score is 9.1, reflecting high exploitability and impact. No patch or vendor advisory information is currently available.
Potential Impact
Successful exploitation allows an attacker to impersonate a legitimate client during TLS 1.3 session resumption, potentially leading to unauthorized access and data compromise. The vulnerability affects confidentiality and integrity but does not impact availability. There are no known exploits in the wild at this time.
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 avoiding session resumption features or deploying additional network-level protections to mitigate risk.
CVE-2026-34873: n/a
Description
A vulnerability in Mbed TLS versions 3. 5. 0 through 4. 0. 0 allows client impersonation during the resumption of a TLS 1. 3 session. This security flaw can be exploited remotely without authentication or user interaction, leading to a critical impact on confidentiality and integrity. The vulnerability is identified as CWE-287, indicating improper authentication. No official patch or remediation details are provided in the current data. There are no known exploits in the wild at this time.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-34873 is a critical vulnerability in Mbed TLS versions 3.5.0 through 4.0.0 that permits client impersonation during TLS 1.3 session resumption. The flaw relates to improper authentication (CWE-287), allowing an unauthenticated remote attacker to impersonate a client, compromising confidentiality and integrity of the TLS session. The CVSS v3.1 base score is 9.1, reflecting high exploitability and impact. No patch or vendor advisory information is currently available.
Potential Impact
Successful exploitation allows an attacker to impersonate a legitimate client during TLS 1.3 session resumption, potentially leading to unauthorized access and data compromise. The vulnerability affects confidentiality and integrity but does not impact availability. There are no known exploits in the wild at this time.
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 avoiding session resumption features or deploying additional network-level protections to mitigate risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-03-31T00:00:00.000Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69cec35ce6bfc5ba1dfb4d55
Added to database: 4/2/2026, 7:28:28 PM
Last enriched: 4/10/2026, 12:03:28 AM
Last updated: 5/20/2026, 9:37:02 PM
Views: 53
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