CVE-2026-123611: rustls before 0.23.46 Key Exchange Downgrade via Unauthenticated ServerHello
Fixed in 0.23.46 · Affected: rustls before 0.23.46 · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 8% of scored CVEs
DescriptionCVE.org
rustls before 0.23.46 contains a key exchange downgrade vulnerability that allows network attackers to poison the per-server-name key-exchange group record via an unauthenticated ServerHello. Attackers can answer one connection with a ServerHello selecting X25519, causing later ClientHellos to send only classical shares and lose post-quantum confidentiality.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- rustls · rustlsbefore 0.23.46
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- rustls
- Published
- November 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-123611 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.