CVE-2026-56855
High
Description
Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Golang Crypto
PublishedSep 2, 2026
First seenSep 2, 2026
Weakness typeCWE-770Allocation of resources without limits
How to fix
Update
- golang crypto0.56.0 or later
- golang.org/x/crypto0.56.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| golang crypto | v < 0.56.0 | 0.56.0 |
| golang.org/x/cryptoGo | v < 0.56.0 | 0.56.0 |
| microsoft azl3_kubevirt_1.7.1-8 | No range specified | — |
| microsoft azl3_packer_1.9.5-18 | No range specified | — |
| microsoft azl3_cf-cli_8.7.11-9 | No range specified | — |
| microsoft azl3_docker-buildx_0.14.0-17 | No range specified | — |
| microsoft azl3_docker-compose_2.27.0-14 | No range specified | — |
| microsoft azl3_kubernetes_1.30.10-30 | No range specified | — |
| microsoft azl3_kubevirt_1.8.4-2 | No range specified | — |
| microsoft azl3_cert-manager_1.12.15-11 | No range specified | — |
| microsoft azl3_cf-cli_8.7.11-8 | No range specified | — |
| microsoft azl3_docker-buildx_0.14.0-16 | No range specified | — |
| microsoft azl3_docker-compose_2.27.0-13 | No range specified | — |
| microsoft azl3_gh_2.62.0-20 | No range specified | — |
| microsoft azl3_kubernetes_1.30.10-27 | No range specified | — |
| microsoft azl3_moby-engine_25.0.3-19 | No range specified | — |
| microsoft azl3_telegraf_1.31.0-28 | No range specified | — |
| microsoft azl3_cert-manager_1.12.15-12 | No range specified | — |
| microsoft azl3_gh_2.98.0-1 | No range specified | — |
| microsoft azl3_kubernetes_1.30.10-29 | No range specified | — |
| microsoft azl3_kubevirt_1.8.4-1 | No range specified | — |
| microsoft azl3_moby-engine_25.0.3-20 | No range specified | — |
| microsoft azl3_packer_1.9.5-20 | No range specified | — |
| microsoft azl3_telegraf_1.31.0-31 | No range specified | — |
| microsoft azl3_packer_1.9.5-21 | No range specified | — |
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