CVE-2025-47913: Golang.org/x/crypto/ssh/agent Denial of Service Vulnerability

HIGH
Advisory Identifier: GHSA-56w8-48fp-6mgv
Share
CVSS 7.5
CWE-617
Published
Advisory Summary

CVE-2025-47913 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-617: Reachable Assertion) affecting Golang.org/x/crypto/ssh/agent libraries in the Go ecosystem. The issue involves golang.org/x/crypto/ssh/agent has a potential denial of service. Remediation is available by upgrading affected packages to version 0.43.0.

CVE-2025-47913 at a Glance

CVE Identifier CVE-2025-47913
GHSA Identifier GHSA-56w8-48fp-6mgv
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-617: Reachable Assertion
Affected Product Golang.org/x/crypto/ssh/agent
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2025-47913

To remediate this vulnerability, upgrade all affected Golang.org/x/crypto/ssh/agent dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

golang.org/x/crypto/ssh/agent fixed: 0.43.0 
Upgrade golang.org/x/crypto/ssh/agent to 0.43.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for golang.org/x/crypto/ssh/agent

How to Check if You Are Affected

To determine whether your application is affected by CVE-2025-47913, inspect your project dependencies for Golang.org/x/crypto/ssh/agent:

inspect dependencies for golang.org/x/crypto/ssh/agent

Analyze the terminal output to locate any version of Golang.org/x/crypto/ssh/agent in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.43.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-617: Reachable Assertion, where the product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary. In Golang.org/x/crypto/ssh/agent, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

SSH clients receiving SSH_AGENT_SUCCESS when expecting a typed response will panic and cause early termination of the client process.

CVE-2025-47913 Affected Golang.org/x/crypto/ssh/agent Versions

1 component(s)
Fixed Versions:
0.43.0
Product / Package Ecosystem Affected Versions Fixed Version
golang.org/x/crypto/ssh/agent
golang/golang.org/x/crypto/ssh/agent
Go
< 0.43.0
0.43.0

References

NVD — CVE-2025-47913 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-47913
Golang.org/x/crypto/ssh/agent Source Repository REPOSITORY
https://github.com/golang/crypto
go.dev/cl/700295 WEB
https://go.dev/cl/700295
go.dev/issue/75178 WEB
https://go.dev/issue/75178
pkg.go.dev/vuln/go-2025-4116 WEB
https://pkg.go.dev/vuln/GO-2025-4116

Frequently Asked Questions

What is CVE-2025-47913?
CVE-2025-47913 is a security vulnerability in Golang.org/x/crypto/ssh/agent involving golang.org/x/crypto/ssh/agent has a potential denial of service under CWE-617: Reachable Assertion.
Which Golang.org/x/crypto/ssh/agent versions are affected?
Affected versions include releases prior to 0.43.0 across affected packages: golang.org/x/crypto/ssh/agent.
What version fixes CVE-2025-47913?
Upgrading to 0.43.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is golang.org/x/crypto/ssh/agent affected?
Yes, golang.org/x/crypto/ssh/agent is affected in releases prior to 0.43.0. Upgrade your dependency to 0.43.0 or later.
What is the CVSS score of CVE-2025-47913?
CVE-2025-47913 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2025-47913?
CVE-2025-47913 is classified under CWE-617: Reachable Assertion (The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.).
How can I check Go dependencies for CVE-2025-47913?
Run the dependency tree command: 'inspect dependencies for golang.org/x/crypto/ssh/agent'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-56w8-48fp-6mgv",
  "modified" : "2026-06-19T14:34:03Z",
  "published" : "2025-11-14T00:30:27Z",
  "aliases" : [ "CVE-2025-47913" ],
  "summary" : "golang.org/x/crypto/ssh/agent has a potential denial of service",
  "details" : "SSH clients receiving SSH_AGENT_SUCCESS when expecting a typed response will panic and cause early termination of the client process.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "golang.org/x/crypto/ssh/agent"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.43.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-47913"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/golang/crypto"
  }, {
    "type" : "WEB",
    "url" : "https://go.dev/cl/700295"
  }, {
    "type" : "WEB",
    "url" : "https://go.dev/issue/75178"
  }, {
    "type" : "WEB",
    "url" : "https://pkg.go.dev/vuln/GO-2025-4116"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-617" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-19T14:34:03Z",
    "nvd_published_at" : "2025-11-13T22:15:51Z"
  }
}