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CVE-2026-39830

Invoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/ssh

Published: May 22, 2026Updated: Aug 6, 2026 Sources: CVE List NVDCWE-119
9.1CRITICAL
NVD MITRE
EPSS Score
0.6%
Top 53.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-119CWE-772

Affected Products

golang.org/x/crypto
oss-projectaka golang x crypto, x/crypto
golang.org/x/crypto/sshLibrary
OSS Libraries / go
golang
oss-project·US
crypto
OSS Libraries

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://go.dev/issue/79564
go.dev
https://groups.google.com/g/golang-announce/c/a082jnz-LvI
groups.google.com
https://go.dev/cl/781640
go.dev
and 44 more references View all →

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