CVE-2026-39829

Invoking pathological RSA/DSA parameters may cause DoS in golang.org/x/crypto/ssh

Published: May 22, 2026Updated: Sep 16, 2026 Sources: CVE List NVD BDUCWE-347

7.5HIGH

Description

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-347 CWE-1284

Affected Products

The Go Project

oss-projectaka go, crypto, golang-google-protobuf

crypto

OSS Libraries

golang.org/x/crypto

oss-projectaka x/crypto, golang x crypto

golang.org/x/crypto/sshLibrary

oss-project·US

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Collection

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References

https://pkg.go.dev/vuln/GO-2026-5018

pkg.go.dev

https://go-review.googlesource.com/c/crypto/+/781641

go-review.googlesource.com

https://go-review.googlesource.com/c/crypto/+/781661

go-review.googlesource.com

and 76 more references View all →

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