Prevent DoS on deadlocked undecided channel in golang.org/x/crypto/ssh
Summary
| CVE | CVE-2026-78662 |
|---|---|
| State | PUBLISHED |
| Assigner | Go |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-02 20:17:37 UTC |
| Updated | 2026-09-04 16:33:34 UTC |
| Description | Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS: 0.003150000 probability, percentile 0.240480000 (date 2026-09-07)
Problem Types: CWE-770 | CWE-770: Allocation of Resources Without Limits or Throttling | CWE-770 CWE-770 Allocation of Resources Without Limits or Throttling
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
NoneAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Golang.orgxcrypto | Golang.org/x/crypto/ssh | affected 0.56.0 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| go.dev/cl/826504 | [email protected] | go.dev | Patch |
| go.dev/issue/81316 | [email protected] | go.dev | Issue Tracking, Vendor Advisory |
| groups.google.com/g/golang-announce/c/1y3fb2np35U | [email protected] | groups.google.com | Mailing List, Vendor Advisory |
| pkg.go.dev/vuln/GO-2026-6354 | [email protected] | pkg.go.dev | Patch, Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Will Mortensen (en)
There are currently no legacy QID mappings associated with this CVE.