Vulnerability-Lookup

GHSA-X2RP-H5QG-FMQG

Vulnerability from github – Published: 2026-09-07 00:30 – Updated: 2026-09-07 00:30

Details

A security flaw has been discovered in mwiede jsch up to 2.28.5. Affected is the function getRevokedKeys of the file src/main/java/com/jcraft/jsch/KnownHosts.java. Performing a manipulation of the argument known_hosts results in improper check for certificate revocation. The attack is possible to be carried out remotely. The attack is considered to have high complexity. The exploitability is told to be difficult. The exploit has been released to the public and may be used for attacks. Upgrading to version 2.28.6 is able to address this issue. The patch is named 194a2f76a5c0f1c3f778565be3fd66bcafc42d23. You should upgrade the affected component.

Severity

3.7 (Low)


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

2.9 (Low)


                  
                    CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

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{
  "affected": [],
  "aliases": [
    "CVE-2026-86231"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-298"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-06T23:17:39Z",
    "severity": "LOW"
  },
  "details": "A security flaw has been discovered in mwiede jsch up to 2.28.5. Affected is the function getRevokedKeys of the file src/main/java/com/jcraft/jsch/KnownHosts.java. Performing a manipulation of the argument known_hosts results in improper check for certificate revocation. The attack is possible to be carried out remotely. The attack is considered to have high complexity. The exploitability is told to be difficult. The exploit has been released to the public and may be used for attacks. Upgrading to version 2.28.6 is able to address this issue. The patch is named 194a2f76a5c0f1c3f778565be3fd66bcafc42d23. You should upgrade the affected component.",
  "id": "GHSA-x2rp-h5qg-fmqg",
  "modified": "2026-09-07T00:30:20Z",
  "published": "2026-09-07T00:30:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-86231"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mwiede/jsch/issues/1091"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mwiede/jsch/pull/1098"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mwiede/jsch/commit/194a2f76a5c0f1c3f778565be3fd66bcafc42d23"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mwiede/jsch"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mwiede/jsch/releases/tag/jsch-2.28.6"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/cve/CVE-2026-86231"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/submit/898485"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/399388"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/399388/cti"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-86231 (GCVE-0-2026-86231)

Vulnerability from cvelistv5 – Published: 2026-09-06 22:45 – Updated: 2026-09-11 20:36 X_Open Source

Title

mwiede jsch KnownHosts.java getRevokedKeys improper check for certificate revocation

Summary

Severity

6.3 (Medium)


                        
                          CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

3.7 (Low)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C

3.7 (Low)


                        
                          CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-11 20:04 UTC

CWE

CWE-299 - Improper Check for Certificate Revocation
CWE-298 - Improper Validation of Certificate Expiration

Assigner

VulDB mitre root

References

9 references

URL	Tags
https://vuldb.com/vuln/399388	vdb-entrytechnical-description
https://vuldb.com/vuln/399388/cti	signaturepermissions-required
https://vuldb.com/cve/CVE-2026-86231	third-party-advisory
https://vuldb.com/submit/898485	third-party-advisory
https://github.com/mwiede/jsch/issues/1091	exploitissue-tracking
https://github.com/mwiede/jsch/pull/1098	issue-trackingpatch
https://github.com/mwiede/jsch/commit/194a2f76a5c…	patch
https://github.com/mwiede/jsch/releases/tag/jsch-2.28.6	patch
https://github.com/mwiede/jsch/	product

Impacted products

1 product

Vendor	Product	Version
mwiede	jsch	Affected: 2.28.0 Affected: 2.28.1 Affected: 2.28.2 Affected: 2.28.3 Affected: 2.28.4 Affected: 2.28.5 Unaffected: 2.28.6 cpe:2.3:a:mwiede:jsch::::::::

Credits

Yu Bao from PayPal Cyber Security Team (VulDB User)

Show details on NVD website

JSON

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{
  "containers": {
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        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-86231",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-11T20:04:55.798482Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-09-11T20:36:19.615Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "cpes": [
            "cpe:2.3:a:mwiede:jsch:*:*:*:*:*:*:*:*"
          ],
          "product": "jsch",
          "vendor": "mwiede",
          "versions": [
            {
              "status": "affected",
              "version": "2.28.0"
            },
            {
              "status": "affected",
              "version": "2.28.1"
            },
            {
              "status": "affected",
              "version": "2.28.2"
            },
            {
              "status": "affected",
              "version": "2.28.3"
            },
            {
              "status": "affected",
              "version": "2.28.4"
            },
            {
              "status": "affected",
              "version": "2.28.5"
            },
            {
              "status": "unaffected",
              "version": "2.28.6"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Yu Bao from PayPal Cyber Security Team (VulDB User)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A security flaw has been discovered in mwiede jsch up to 2.28.5. Affected is the function getRevokedKeys of the file src/main/java/com/jcraft/jsch/KnownHosts.java. Performing a manipulation of the argument known_hosts results in improper check for certificate revocation. The attack is possible to be carried out remotely. The attack is considered to have high complexity. The exploitability is told to be difficult. The exploit has been released to the public and may be used for attacks. Upgrading to version 2.28.6 is able to address this issue. The patch is named 194a2f76a5c0f1c3f778565be3fd66bcafc42d23. You should upgrade the affected component."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P",
            "version": "4.0"
          }
        },
        {
          "cvssV3_1": {
            "baseScore": 3.7,
            "baseSeverity": "LOW",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C",
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        {
          "cvssV3_0": {
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            "baseSeverity": "LOW",
            "vectorString": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C",
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        },
        {
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            "vectorString": "AV:N/AC:H/Au:N/C:N/I:P/A:N/E:POC/RL:OF/RC:C",
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      },
      "references": [
        {
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          "tags": [
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          "url": "https://vuldb.com/vuln/399388"
        },
        {
          "name": "VDB-399388 | CTI Indicators (IOB, IOC, TTP, IOA)",
          "tags": [
            "signature",
            "permissions-required"
          ],
          "url": "https://vuldb.com/vuln/399388/cti"
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          "tags": [
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          "url": "https://vuldb.com/cve/CVE-2026-86231"
        },
        {
          "name": "Submit #898485 | mwiede jsch 2.28.4 Cert Revocation Type String Bypass",
          "tags": [
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          "url": "https://vuldb.com/submit/898485"
        },
        {
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        {
          "tags": [
            "issue-tracking",
            "patch"
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          "url": "https://github.com/mwiede/jsch/pull/1098"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/mwiede/jsch/commit/194a2f76a5c0f1c3f778565be3fd66bcafc42d23"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/mwiede/jsch/releases/tag/jsch-2.28.6"
        },
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          "tags": [
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          "url": "https://github.com/mwiede/jsch/"
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      "tags": [
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          "value": "Advisory disclosed"
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          "lang": "en",
          "time": "2026-09-06T02:00:00.000Z",
          "value": "VulDB entry created"
        },
        {
          "lang": "en",
          "time": "2026-09-06T10:09:53.000Z",
          "value": "VulDB entry last update"
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      "title": "mwiede jsch KnownHosts.java getRevokedKeys improper check for certificate revocation",
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  "cveMetadata": {
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    "dateReserved": "2026-09-06T08:04:47.571Z",
    "dateUpdated": "2026-09-11T20:36:19.615Z",
    "state": "PUBLISHED"
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}

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.

Detection rules are retrieved from Rulezet.

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.

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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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GHSA-X2RP-H5QG-FMQG

CVE-2026-86231 (GCVE-0-2026-86231)

Tags

Sightings

Nomenclature

Related by attack behaviour