CVE-2026-56862: Limit handshake messages we are willing to accept post-handshake in crypto/tls
CSIRTS triage
- What
- The crypto/tls module fails to limit handshake messages after the handshake is complete, allowing resource exhaustion.
- Who is affected
- All Go applications using TLS that accept post-handshake messages.
- Urgency
- High priority; CVSS 7.5 indicates significant impact on TLS connection handling.
- Action
- Update to the patched Go version addressing CVE-2026-56862.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56862
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-568620.48% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-56862 | coverage & exploitation status | NVD · CVE.org |
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