Vulnerability-Lookup

SUSE-SU-2026:23841-1

Vulnerability from csaf_suse - Published: 2026-09-15 07:07 - Updated: 2026-09-27 11:06

Summary

Security update for google-osconfig-agent

Severity

Important

Notes

Title of the patch: Security update for google-osconfig-agent

Description of the patch: This update for google-osconfig-agent fixes the following issue: - CVE-2026-56854: golang.org/x/crypto/ssh: authentication bypass and deadlocks in the crypto/ssh library (bsc#1278597). - CVE-2026-56855: golang.org/x/crypto/ssh: authentication bypass and deadlocks in the crypto/ssh library (bsc#1278597). - CVE-2026-78662: golang.org/x/crypto/ssh: authentication bypass and deadlocks in the crypto/ssh library (bsc#1278597).

Patchnames: SUSE-SLE-Micro-6.0-900

CVE-2026-56854

8.1 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Affected products

Recommended 3 products

Product	Version	Remediation
Unresolved product id: SUSE Linux Micro 6.0:google-osconfig-agent-0:20260908.00-2.1.aarch64	—	Vendor Fix
Unresolved product id: SUSE Linux Micro 6.0:google-osconfig-agent-0:20260908.00-2.1.s390x	—	Vendor Fix
Unresolved product id: SUSE Linux Micro 6.0:google-osconfig-agent-0:20260908.00-2.1.x86_64	—	Vendor Fix

Threats

Impact important

CVE-2026-56855

7.5 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Recommended 3 products, the same list as for CVE-2026-56854

Threats

Impact important

CVE-2026-78662

7.5 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

Recommended 3 products, the same list as for CVE-2026-56854

Threats

Impact important

References

17 references

URL	Category
https://www.suse.com/support/security/rating/	external
https://ftp.suse.com/pub/projects/security/csaf/s…	self
https://www.suse.com/support/update/announcement/…	self
https://lists.suse.com/pipermail/sle-updates/2026…	self
https://bugzilla.suse.com/1278597	self
https://www.suse.com/security/cve/CVE-2026-56854/	self
https://www.suse.com/security/cve/CVE-2026-56855/	self
https://www.suse.com/security/cve/CVE-2026-78662/	self
https://www.suse.com/security/cve/CVE-2026-56854	external
https://bugzilla.suse.com/1278446	external
https://bugzilla.suse.com/1280553	external
https://www.suse.com/security/cve/CVE-2026-56855	external
https://bugzilla.suse.com/1278446	external
https://bugzilla.suse.com/1280553	external
https://www.suse.com/security/cve/CVE-2026-78662	external
https://bugzilla.suse.com/1278446	external
https://bugzilla.suse.com/1280553	external

JSON

To clipboard

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          "text": "The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client\u0027s remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.",
          "title": "CVE description"
        }
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}

CVE-2026-56854 (GCVE-0-2026-56854)

Vulnerability from cvelistv5 – Published: 2026-08-28 15:14 – Updated: 2026-08-28 20:17

Title

Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh

Summary

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-28 20:16 UTC

CWE

CWE-863 - Incorrect Authorization

Assigner

Go CNA under the Google root

CNA scorecard E 42/100 over 75 records in the last 180 days details

References

3 references

URL	Tags
https://go.dev/issue/80213
https://go.dev/cl/797040
https://pkg.go.dev/vuln/GO-2026-6303

Impacted products

1 product

Vendor	Product	Version
golang.org/x/crypto	golang.org/x/crypto/ssh	Affected: 0 , < 0.55.0 (semver)

Credits

Longwei Wang (@gn00295120)

Show details on NVD website

JSON

To clipboard

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              "confidentialityImpact": "HIGH",
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-28T20:17:17.397Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "golang.org/x/crypto/ssh",
          "product": "golang.org/x/crypto/ssh",
          "programRoutines": [
            {
              "name": "connection.serverAuthenticate"
            },
            {
              "name": "NewServerConn"
            }
          ],
          "vendor": "golang.org/x/crypto",
          "versions": [
            {
              "lessThan": "0.55.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Longwei Wang (@gn00295120)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client\u0027s remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-863: Incorrect Authorization",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-28T15:14:26.918Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://go.dev/issue/80213"
        },
        {
          "url": "https://go.dev/cl/797040"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6303"
        }
      ],
      "title": "Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-56854",
    "datePublished": "2026-08-28T15:14:26.918Z",
    "dateReserved": "2026-06-23T15:10:49.353Z",
    "dateUpdated": "2026-08-28T20:17:17.397Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-56855 (GCVE-0-2026-56855)

Vulnerability from cvelistv5 – Published: 2026-09-02 19:37 – Updated: 2026-09-03 14:14

Title

Prevent DoS on deadlocked established channel in golang.org/x/crypto/ssh

Summary

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-03 14:13 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

Go CNA under the Google root

CNA scorecard E 42/100 over 75 records in the last 180 days details

References

4 references

URL	Tags
https://go.dev/issue/81317
https://go.dev/cl/826524
https://groups.google.com/g/golang-announce/c/1y3…
https://pkg.go.dev/vuln/GO-2026-6355

Impacted products

1 product

Vendor	Product	Version
golang.org/x/crypto	golang.org/x/crypto/ssh	Affected: 0 , < 0.56.0 (semver)

Credits

Will Mortensen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-56855",
                "options": [
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                    "Exploitation": "none"
                  },
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                    "Automatable": "yes"
                  },
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                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-03T14:13:54.397574Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-770",
                "description": "CWE-770 Allocation of Resources Without Limits or Throttling",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-03T14:14:40.169Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "golang.org/x/crypto/ssh",
          "product": "golang.org/x/crypto/ssh",
          "programRoutines": [
            {
              "name": "channel.handlePacket"
            },
            {
              "name": "Dial"
            },
            {
              "name": "NewClientConn"
            },
            {
              "name": "NewControlClientConn"
            },
            {
              "name": "NewServerConn"
            }
          ],
          "vendor": "golang.org/x/crypto",
          "versions": [
            {
              "lessThan": "0.56.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Will Mortensen"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-02T19:37:05.807Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
        "shortName": "Go"
      },
      "references": [
        {
          "url": "https://go.dev/issue/81317"
        },
        {
          "url": "https://go.dev/cl/826524"
        },
        {
          "url": "https://groups.google.com/g/golang-announce/c/1y3fb2np35U"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6355"
        }
      ],
      "title": "Prevent DoS on deadlocked established channel in golang.org/x/crypto/ssh"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-56855",
    "datePublished": "2026-09-02T19:37:05.807Z",
    "dateReserved": "2026-06-23T15:10:49.353Z",
    "dateUpdated": "2026-09-03T14:14:40.169Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-78662 (GCVE-0-2026-78662)

Vulnerability from cvelistv5 – Published: 2026-09-02 19:37 – Updated: 2026-09-03 13:20

Title

Prevent DoS on deadlocked undecided channel in golang.org/x/crypto/ssh

Summary

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.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-03 13:19 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

Go CNA under the Google root

CNA scorecard E 42/100 over 75 records in the last 180 days details

References

4 references

URL	Tags
https://go.dev/issue/81316
https://go.dev/cl/826504
https://groups.google.com/g/golang-announce/c/1y3…
https://pkg.go.dev/vuln/GO-2026-6354

Impacted products

1 product

Vendor	Product	Version
golang.org/x/crypto	golang.org/x/crypto/ssh	Affected: 0 , < 0.56.0 (semver)

Credits

Will Mortensen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-78662",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-03T13:19:47.340520Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-770",
                "description": "CWE-770 Allocation of Resources Without Limits or Throttling",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-03T13:20:12.263Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://pkg.go.dev",
          "defaultStatus": "unaffected",
          "packageName": "golang.org/x/crypto/ssh",
          "product": "golang.org/x/crypto/ssh",
          "programRoutines": [
            {
              "name": "channel.handlePacket"
            },
            {
              "name": "channel.responseMessageReceived"
            },
            {
              "name": "channel.Accept"
            },
            {
              "name": "Dial"
            },
            {
              "name": "NewClientConn"
            },
            {
              "name": "NewControlClientConn"
            },
            {
              "name": "NewServerConn"
            }
          ],
          "vendor": "golang.org/x/crypto",
          "versions": [
            {
              "lessThan": "0.56.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Will Mortensen"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Previously, a channel registered in the mux\u0027s chanList is not usable until it is established. A malicious peer was able flood the channel\u0027s 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."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-02T19:37:05.741Z",
        "orgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
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      },
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          "url": "https://go.dev/issue/81316"
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          "url": "https://go.dev/cl/826504"
        },
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          "url": "https://groups.google.com/g/golang-announce/c/1y3fb2np35U"
        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-6354"
        }
      ],
      "title": "Prevent DoS on deadlocked undecided channel in golang.org/x/crypto/ssh"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "1bb62c36-49e3-4200-9d77-64a1400537cc",
    "assignerShortName": "Go",
    "cveId": "CVE-2026-78662",
    "datePublished": "2026-09-02T19:37:05.741Z",
    "dateReserved": "2026-08-24T23:36:15.738Z",
    "dateUpdated": "2026-09-03T13:20:12.263Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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SUSE-SU-2026:23841-1

CVE-2026-56854 (GCVE-0-2026-56854)

CVE-2026-56855 (GCVE-0-2026-56855)

CVE-2026-78662 (GCVE-0-2026-78662)

Tags

Sightings

Nomenclature

Vulnerability timeline

Related by attack behaviour