CVE-2026-34873
Mbed TLS 3.5.0 through 4.0.0 vulnerability
Mbed · 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.
MSRC advisory May 19, 2026
Alert details
- Source feed
- Microsoft MSRC
- CVE ID
- CVE-2026-34873
- Affected products
- 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. · An 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. · An
What happened
Information published.
What it means for your business
An 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. (CVE-2026-34873) was added to Microsoft’s security update guidance. Information published. PremierePC tracks MSRC advisories for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
EPSS probability
0.24%
Sources
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