# CVE-2026-56862: GO-2026-6090 - Limit handshake messages we are willing to accept post-handshake in crypto/tls

Source: https://junglewise.ai/threats/cve-2026-56862-go-2026-6090-limit-handshake-messages-we-are-willing-to-accept  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-13  
License: CC BY 4.0 with a link back

CVE-2026-56862 · Severity: info · Published 2026-08-13

Limit handshake messages we are willing to accept post-handshake in crypto/tls

Technologies: [stdlib (Go)](https://junglewise.ai/threats/technologies/go-stdlib). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-56862 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-56862 being exploited in the wild.

**How severe is CVE-2026-56862?** Informational severity, published 13 August 2026.

**Which products and versions are affected?** stdlib (Go) SEMVER:introduced=0,fixed=1.25.13,introduced=1.26.0-0,fixed=1.26.6,introduced=1.27.0-0,fixed=1.27.0-rc.3.

**Is there a fix for CVE-2026-56862?** Yes. stdlib (Go): upgrade to 1.27.0-rc.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-56862?** Check whether you run stdlib (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- stdlib (Go): upgrade to 1.27.0-rc.3 or later

  ```sh
  go get stdlib@v1.27.0-rc.3
  ```


## Affected products

- stdlib (Go) SEMVER:introduced=0,fixed=1.25.13,introduced=1.26.0-0,fixed=1.26.6,introduced=1.27.0-0,fixed=1.27.0-rc.3

## Identifiers

- CVE-2026-56862
- GO-2026-6090

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