High severity · published May 22, 2026
CVE-2026-39829
Invoking pathological RSA/DSA parameters may cause DoS in golang.org/x/crypto/ssh
7.5
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GO
golang.org/x/crypto/ssh · golang.org/x/crypto
before 0.52.0 · source: vendor
CR
Crypto · Golang
before 0.52.0 · source: NVD
AI
Assisted Installer for Red Hat OpenShift Container Platform 2 · Red Hat
All versions, or not specified · source: CISA
CO
Cluster Observability Operator 1.5.0 · Red Hat
All versions, or not specified · source: CISA
CC
Confidential Compute Attestation · Red Hat
All versions, or not specified · source: CISA
C4
Cryostat 4 on RHEL 9 · Red Hat
All versions, or not specified · source: CISA
DO
DevWorkspace Operator 0.42 · Red Hat
All versions, or not specified · source: CISA
ES
External Secrets Operator for Red Hat OpenShift · Red Hat
All versions, or not specified · source: CISA
LS
Logging Subsystem for Red Hat OpenShift · Red Hat
All versions, or not specified · source: CISA
ME
Multicluster Engine for Kubernetes · Red Hat
All versions, or not specified · source: CISA
OA
OpenShift API for Data Protection · Red Hat
All versions, or not specified · source: CISA
OA
OpenShift API for Data Protection 1.3 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-39829
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-39829
Issue Tracking
https://go.dev/cl/781641
Issue Tracking
https://go.dev/cl/781661
Issue Tracking
https://go.dev/issue/79565
Mailing List
https://groups.google.com/g/golang-announce/c/a082jnz-LvI
Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-5018
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:26546
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