{"api_version":"1","generated_at":"2026-09-07T09:10:33+00:00","cve":"CVE-2026-86231","urls":{"html":"https://cve.report/CVE-2026-86231","api":"https://cve.report/api/cve/CVE-2026-86231.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-86231","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-86231"},"summary":{"title":"mwiede jsch KnownHosts.java getRevokedKeys improper check for certificate revocation","description":"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.","state":"PUBLISHED","assigner":"VulDB","published_at":"2026-09-06 23:17:39","updated_at":"2026-09-06 23:17:39"},"problem_types":["CWE-298","CWE-299","CWE-299 Improper Check for Certificate Revocation","CWE-298 Improper Validation of Certificate Expiration"],"metrics":[{"version":"4.0","source":"cna@vuldb.com","type":"Secondary","score":"2.9","severity":"LOW","vector":"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","data":{"version":"4.0","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/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","baseScore":2.9,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}},{"version":"4.0","source":"CNA","type":"DECLARED","score":"6.3","severity":"MEDIUM","vector":"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","data":{"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"}},{"version":"3.1","source":"cna@vuldb.com","type":"Primary","score":"3.7","severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","baseScore":3.7,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"3.7","severity":"LOW","vector":"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","data":{"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","version":"3.1"}},{"version":"3.0","source":"CNA","type":"DECLARED","score":"3.7","severity":"LOW","vector":"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","data":{"baseScore":3.7,"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","version":"3.0"}},{"version":"2.0","source":"cna@vuldb.com","type":"Secondary","score":"2.6","severity":"","vector":"AV:N/AC:H/Au:N/C:N/I:P/A:N","data":{"version":"2.0","vectorString":"AV:N/AC:H/Au:N/C:N/I:P/A:N","baseScore":2.6,"accessVector":"NETWORK","accessComplexity":"HIGH","authentication":"NONE","confidentialityImpact":"NONE","integrityImpact":"PARTIAL","availabilityImpact":"NONE"}},{"version":"2.0","source":"CNA","type":"DECLARED","score":"2.6","severity":"","vector":"AV:N/AC:H/Au:N/C:N/I:P/A:N/E:POC/RL:OF/RC:C","data":{"baseScore":2.6,"vectorString":"AV:N/AC:H/Au:N/C:N/I:P/A:N/E:POC/RL:OF/RC:C","version":"2.0"}}],"references":[{"url":"https://vuldb.com/vuln/399388","name":"https://vuldb.com/vuln/399388","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mwiede/jsch/pull/1098","name":"https://github.com/mwiede/jsch/pull/1098","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://vuldb.com/submit/898485","name":"https://vuldb.com/submit/898485","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mwiede/jsch/","name":"https://github.com/mwiede/jsch/","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mwiede/jsch/commit/194a2f76a5c0f1c3f778565be3fd66bcafc42d23","name":"https://github.com/mwiede/jsch/commit/194a2f76a5c0f1c3f778565be3fd66bcafc42d23","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mwiede/jsch/releases/tag/jsch-2.28.6","name":"https://github.com/mwiede/jsch/releases/tag/jsch-2.28.6","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mwiede/jsch/issues/1091","name":"https://github.com/mwiede/jsch/issues/1091","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://vuldb.com/vuln/399388/cti","name":"https://vuldb.com/vuln/399388/cti","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://vuldb.com/cve/CVE-2026-86231","name":"https://vuldb.com/cve/CVE-2026-86231","refsource":"cna@vuldb.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-86231","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86231","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"mwiede","product":"jsch","version":"affected 2.28.0","platforms":[]},{"source":"CNA","vendor":"mwiede","product":"jsch","version":"affected 2.28.1","platforms":[]},{"source":"CNA","vendor":"mwiede","product":"jsch","version":"affected 2.28.2","platforms":[]},{"source":"CNA","vendor":"mwiede","product":"jsch","version":"affected 2.28.3","platforms":[]},{"source":"CNA","vendor":"mwiede","product":"jsch","version":"affected 2.28.4","platforms":[]},{"source":"CNA","vendor":"mwiede","product":"jsch","version":"affected 2.28.5","platforms":[]},{"source":"CNA","vendor":"mwiede","product":"jsch","version":"unaffected 2.28.6","platforms":[]}],"timeline":[{"source":"CNA","time":"2026-09-06T00:00:00.000Z","lang":"en","value":"Advisory disclosed"},{"source":"CNA","time":"2026-09-06T02:00:00.000Z","lang":"en","value":"VulDB entry created"},{"source":"CNA","time":"2026-09-06T10:09:53.000Z","lang":"en","value":"VulDB entry last update"}],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"Yu Bao from PayPal Cyber Security Team (VulDB User)","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"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","version":"3.1"}},{"cvssV3_0":{"baseScore":3.7,"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","version":"3.0"}},{"cvssV2_0":{"baseScore":2.6,"vectorString":"AV:N/AC:H/Au:N/C:N/I:P/A:N/E:POC/RL:OF/RC:C","version":"2.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-299","description":"Improper Check for Certificate Revocation","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-298","description":"Improper Validation of Certificate Expiration","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-06T22:45:12.262Z","orgId":"1af790b2-7ee1-4545-860a-a788eba489b5","shortName":"VulDB"},"references":[{"name":"VDB-399388 | mwiede jsch KnownHosts.java getRevokedKeys improper check for certificate revocation","tags":["vdb-entry","technical-description"],"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"},{"name":"CVE-2026-86231 | CVE Analysis and Report","tags":["third-party-advisory"],"url":"https://vuldb.com/cve/CVE-2026-86231"},{"name":"Submit #898485 | mwiede jsch 2.28.4 Cert Revocation Type String Bypass","tags":["third-party-advisory"],"url":"https://vuldb.com/submit/898485"},{"tags":["exploit","issue-tracking"],"url":"https://github.com/mwiede/jsch/issues/1091"},{"tags":["issue-tracking","patch"],"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"},{"tags":["product"],"url":"https://github.com/mwiede/jsch/"}],"tags":["x_open-source"],"timeline":[{"lang":"en","time":"2026-09-06T00:00:00.000Z","value":"Advisory disclosed"},{"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"}],"title":"mwiede jsch KnownHosts.java getRevokedKeys improper check for certificate revocation","x_generator":["VulDB PVTS v202609"]}},"cveMetadata":{"assignerOrgId":"1af790b2-7ee1-4545-860a-a788eba489b5","assignerShortName":"VulDB","cveId":"CVE-2026-86231","datePublished":"2026-09-06T22:45:12.262Z","dateReserved":"2026-09-06T08:04:47.571Z","dateUpdated":"2026-09-06T22:45:12.262Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-06 23:17:39","lastModifiedDate":"2026-09-06 23:17:39","problem_types":["CWE-298","CWE-299","CWE-299 Improper Check for Certificate Revocation","CWE-298 Improper Validation of Certificate Expiration"],"metrics":{"cvssMetricV40":[{"source":"cna@vuldb.com","type":"Secondary","cvssData":{"version":"4.0","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/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","baseScore":2.9,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"cna@vuldb.com","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","baseScore":3.7,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.2,"impactScore":1.4}],"cvssMetricV2":[{"source":"cna@vuldb.com","type":"Secondary","cvssData":{"version":"2.0","vectorString":"AV:N/AC:H/Au:N/C:N/I:P/A:N","baseScore":2.6,"accessVector":"NETWORK","accessComplexity":"HIGH","authentication":"NONE","confidentialityImpact":"NONE","integrityImpact":"PARTIAL","availabilityImpact":"NONE"},"baseSeverity":"LOW","exploitabilityScore":4.9,"impactScore":2.9,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"86231","Ordinal":"1","Title":"mwiede jsch KnownHosts.java getRevokedKeys improper check for ce","CVE":"CVE-2026-86231","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"86231","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"mwiede jsch KnownHosts.java getRevokedKeys improper check for ce"}]}}}