CVE-2026-34873
CRITICALCVSS 9.1/10EPSS 0.24%
Last modified
CVE-2026-34873 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. An issue was discovered in Mbed TLS 3.5.0 through 4.0.0. Client impersonation can occur while resuming a TLS 1.3 session.. EPSS estimates a 0.24% chance of exploitation in the next 30 days.
Description
An issue was discovered in Mbed TLS 3.5.0 through 4.0.0. Client impersonation can occur while resuming a TLS 1.3 session.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Trustedfirmware | Mbed Tls | >= 3.5.0, < 3.6.6 |
| Trustedfirmware | Mbed Tls | >= 4.0.0, < 4.1.0 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-34873?
An issue was discovered in Mbed TLS 3.5.0 through 4.0.0. Client impersonation can occur while resuming a TLS 1.3 session.
How severe is CVE-2026-34873?
CVE-2026-34873 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 0.24% probability of exploitation in the next 30 days.
How do I fix CVE-2026-34873?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
Are you affected by CVE-2026-34873?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST