{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-59849", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "state": "PUBLISHED", "assignerShortName": "redhat", "dateReserved": "2026-07-07T15:40:24.561Z", "datePublished": "2026-07-21T14:08:15.016Z", "dateUpdated": "2026-08-19T04:57:42.066Z"}, "containers": {"cna": {"title": "Libssh: libssh: denial of service via automatic certificate authentication loop", "metrics": [{"other": {"content": {"value": "Low", "namespace": "https://access.redhat.com/security/updates/classification/"}, "type": "Red Hat severity rating"}}, {"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 3.1, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}, "format": "CVSS"}], "descriptions": [{"lang": "en", "value": "A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service."}], "affected": [{"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 10", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libssh", "defaultStatus": "affected", "versions": [{"version": "0:0.12.0-3.el10_2", "lessThan": "*", "versionType": "rpm", "status": "unaffected"}], "cpes": ["cpe:/o:redhat:enterprise_linux:10.2"]}, {"vendor": "Red Hat", "product": "Red Hat Hardened Images", "collectionURL": "https://catalog.redhat.com/software/containers/", "packageName": "libssh-main", "defaultStatus": "affected", "versions": [{"version": "0.12.1-4.hum1", "lessThan": "*", "versionType": "rpm", "status": "unaffected"}], "cpes": ["cpe:/a:redhat:hummingbird:1"]}, {"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libssh", "defaultStatus": "unaffected", "cpes": ["cpe:/o:redhat:enterprise_linux:8"]}, {"vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "packageName": "libssh", "defaultStatus": "unaffected", "cpes": ["cpe:/o:redhat:enterprise_linux:9"]}], "references": [{"url": "https://access.redhat.com/errata/RHSA-2026:42922", "name": "RHSA-2026:42922", "tags": ["vendor-advisory", "x_refsource_REDHAT"]}, {"url": "https://access.redhat.com/errata/RHSA-2026:55855", "name": "RHSA-2026:55855", "tags": ["vendor-advisory", "x_refsource_REDHAT"]}, {"url": "https://access.redhat.com/security/cve/CVE-2026-59849", "tags": ["vdb-entry", "x_refsource_REDHAT"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2498182", "name": "RHBZ#2498182", "tags": ["issue-tracking", "x_refsource_REDHAT"]}], "datePublic": "2026-07-21T14:03:21.506Z", "problemTypes": [{"descriptions": [{"cweId": "CWE-835", "description": "Loop with Unreachable Exit Condition ('Infinite Loop')", "lang": "en", "type": "CWE"}]}], "x_redhatCweChain": "CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')", "workarounds": [{"lang": "en", "value": "Do not connect to untrusted SSH servers and do not use certificates until patched."}], "timeline": [{"lang": "en", "time": "2026-04-29T10:03:47.442Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-07-21T14:03:21.506Z", "value": "Made public."}], "credits": [{"lang": "en", "value": "Red Hat would like to thank AISLE Research for reporting this issue."}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-08-19T04:57:42.066Z"}, "x_generator": {"engine": "cvelib 1.8.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-07-22T14:31:02.938864Z", "id": "CVE-2026-59849", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-07-22T14:31:13.977Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-59849", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-07-22T14:31:02.938864Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-07-22T14:31:09.232Z"}}], "cna": {"title": "Libssh: libssh: denial of service via automatic certificate authentication loop", "credits": [{"lang": "en", "value": "Red Hat would like to thank AISLE Research for reporting this issue."}], "metrics": [{"other": {"type": "Red Hat severity rating", "content": {"value": "Low", "namespace": "https://access.redhat.com/security/updates/classification/"}}}, {"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 3.1, "attackVector": "NETWORK", "baseSeverity": "LOW", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "LOW", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}}], "affected": [{"cpes": ["cpe:/o:redhat:enterprise_linux:10.2"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 10", "versions": [{"status": "unaffected", "version": "0:0.12.0-3.el10_2", "lessThan": "*", "versionType": "rpm"}], "packageName": "libssh", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:hummingbird:1"], "vendor": "Red Hat", "product": "Red Hat Hardened Images", "versions": [{"status": "unaffected", "version": "0.12.1-4.hum1", "lessThan": "*", "versionType": "rpm"}], "packageName": "libssh-main", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:8"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8", "packageName": "libssh", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:9"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9", "packageName": "libssh", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}], "timeline": [{"lang": "en", "time": "2026-04-29T10:03:47.442Z", "value": "Reported to Red Hat."}, {"lang": "en", "time": "2026-07-21T14:03:21.506Z", "value": "Made public."}], "datePublic": "2026-07-21T14:03:21.506Z", "references": [{"url": "https://access.redhat.com/errata/RHSA-2026:42922", "name": "RHSA-2026:42922", "tags": ["vendor-advisory", "x_refsource_REDHAT"]}, {"url": "https://access.redhat.com/errata/RHSA-2026:55855", "name": "RHSA-2026:55855", "tags": ["vendor-advisory", "x_refsource_REDHAT"]}, {"url": "https://access.redhat.com/security/cve/CVE-2026-59849", "tags": ["vdb-entry", "x_refsource_REDHAT"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2498182", "name": "RHBZ#2498182", "tags": ["issue-tracking", "x_refsource_REDHAT"]}], "workarounds": [{"lang": "en", "value": "Do not connect to untrusted SSH servers and do not use certificates until patched."}], "x_generator": {"engine": "cvelib 1.8.0"}, "descriptions": [{"lang": "en", "value": "A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-835", "description": "Loop with Unreachable Exit Condition ('Infinite Loop')"}]}], "providerMetadata": {"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat", "dateUpdated": "2026-08-19T04:57:42.066Z"}, "x_redhatCweChain": "CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')"}}, "cveMetadata": {"cveId": "CVE-2026-59849", "state": "PUBLISHED", "dateUpdated": "2026-08-19T04:57:42.066Z", "dateReserved": "2026-07-07T15:40:24.561Z", "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "datePublished": "2026-07-21T14:08:15.016Z", "assignerShortName": "redhat"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:10.2"], "defaultStatus": "affected", "packageName": "libssh", "product": "Red Hat Enterprise Linux 10", "vendor": "Red Hat", "versions": [{"lessThan": "*", "status": "unaffected", "version": "0:0.12.0-3.el10_2", "versionType": "rpm"}]}, {"collectionURL": "https://catalog.redhat.com/software/containers/", "cpes": ["cpe:/a:redhat:hummingbird:1"], "defaultStatus": "affected", "packageName": "libssh-main", "product": "Red Hat Hardened Images", "vendor": "Red Hat", "versions": [{"lessThan": "*", "status": "unaffected", "version": "0.12.1-4.hum1", "versionType": "rpm"}]}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:8"], "defaultStatus": "unaffected", "packageName": "libssh", "product": "Red Hat Enterprise Linux 8", "vendor": "Red Hat"}, {"collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "cpes": ["cpe:/o:redhat:enterprise_linux:9"], "defaultStatus": "unaffected", "packageName": "libssh", "product": "Red Hat Enterprise Linux 9", "vendor": "Red Hat"}], "source": "secalert@redhat.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:libssh:libssh:-:*:*:*:*:*:*:*", "matchCriteriaId": "9B0EB43D-D594-43B0-AB33-5E8E1A6C8BEF", "vulnerable": true}, {"criteria": "cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*", "matchCriteriaId": "87DEB507-5B64-47D7-9A50-3B87FD1E571F", "vulnerable": true}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*", "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service."}], "id": "CVE-2026-59849", "lastModified": "2026-08-19T05:17:05.210", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 3.1, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 1.6, "impactScore": 1.4, "source": "secalert@redhat.com", "type": "Secondary"}, {"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-59849", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-22T14:31:02.938864Z", "version": "2.0.3"}}]}, "published": "2026-07-21T15:16:37.647", "references": [{"source": "secalert@redhat.com", "tags": ["Issue Tracking"], "url": "https://access.redhat.com/errata/RHSA-2026:42922"}, {"source": "secalert@redhat.com", "url": "https://access.redhat.com/errata/RHSA-2026:55855"}, {"source": "secalert@redhat.com", "tags": ["Vendor Advisory"], "url": "https://access.redhat.com/security/cve/CVE-2026-59849"}, {"source": "secalert@redhat.com", "tags": ["Issue Tracking", "Vendor Advisory"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2498182"}], "sourceIdentifier": "secalert@redhat.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-835"}], "source": "secalert@redhat.com", "type": "Secondary"}]}

{"acknowledgement": "Red Hat would like to thank AISLE Research for reporting this issue.", "bugzilla": {"description": "libssh: libssh: denial of service via automatic certificate authentication loop", "id": "2498182", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2498182"}, "csaw": false, "cvss3": {"cvss3_base_score": "3.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-835", "details": ["A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause libssh clients to loop indefinitely when configured certificates are missing or repeatedly rejected by a server, leading to denial of service."], "mitigation": {"lang": "en:us", "value": "Do not connect to untrusted SSH servers and do not use certificates until patched."}, "name": "CVE-2026-59849", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "libssh", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "libssh", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "libssh", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "impact": "low", "package_name": "libssh", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-07-21T14:03:21Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-59849\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-59849"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": null}], "product": "libssh", "vendor": "libssh"}, {"configurations": [{"platform": null, "status": "affected", "versions": null}], "enrichment": {"confidence": 100.0, "confidence_source": "manual", "scores": [{"score": 100.0, "source": "manual"}]}, "original": {"product": "Red Hat Enterprise Linux 10", "source": "cna", "vendor": "Red Hat"}, "product": "enterprise_linux", "vendor": "redhat"}, {"configurations": [{"platform": null, "status": "affected", "versions": null}], "enrichment": {"confidence": 83.0, "confidence_source": "matching", "scores": [{"score": 83.0, "source": "matching"}]}, "original": {"product": "Red Hat Hardened Images", "source": "cna", "vendor": "Red Hat"}, "product": "hardened_images", "vendor": "redhat"}], "created": "2026-07-27T20:40:50.308397+00:00", "updated": "2026-07-30T17:30:17.244509+00:00", "vendors": ["libssh", "libssh$PRODUCT$libssh", "redhat", "redhat$PRODUCT$enterprise_linux", "redhat$PRODUCT$hardened_images"]}