CVE-2021-20230

{"containers": {"cna": {"affected": [{"product": "stunnel", "vendor": "n/a", "versions": [{"status": "affected", "version": "stunnel 5.57"}]}], "descriptions": [{"lang": "en", "value": "A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality."}], "problemTypes": [{"descriptions": [{"cweId": "CWE-295", "description": "CWE-295", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"dateUpdated": "2021-05-26T09:06:16.000Z", "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "shortName": "redhat"}, "references": [{"tags": ["x_refsource_MISC"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226"}, {"tags": ["x_refsource_MISC"], "url": "https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9"}, {"name": "GLSA-202105-02", "tags": ["vendor-advisory", "x_refsource_GENTOO"], "url": "https://security.gentoo.org/glsa/202105-02"}], "x_legacyV4Record": {"CVE_data_meta": {"ASSIGNER": "secalert@redhat.com", "ID": "CVE-2021-20230", "STATE": "PUBLIC"}, "affects": {"vendor": {"vendor_data": [{"product": {"product_data": [{"product_name": "stunnel", "version": {"version_data": [{"version_value": "stunnel 5.57"}]}}]}, "vendor_name": "n/a"}]}}, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": {"description_data": [{"lang": "eng", "value": "A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "eng", "value": "CWE-295"}]}]}, "references": {"reference_data": [{"name": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226", "refsource": "MISC", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226"}, {"name": "https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9", "refsource": "MISC", "url": "https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9"}, {"name": "GLSA-202105-02", "refsource": "GENTOO", "url": "https://security.gentoo.org/glsa/202105-02"}]}}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-03T17:30:07.599Z"}, "title": "CVE Program Container", "references": [{"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9"}, {"name": "GLSA-202105-02", "tags": ["vendor-advisory", "x_refsource_GENTOO", "x_transferred"], "url": "https://security.gentoo.org/glsa/202105-02"}]}]}, "cveMetadata": {"assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749", "assignerShortName": "redhat", "cveId": "CVE-2021-20230", "datePublished": "2021-02-23T16:34:39.000Z", "dateReserved": "2020-12-17T00:00:00.000Z", "dateUpdated": "2024-08-03T17:30:07.599Z", "state": "PUBLISHED"}, "dataType": "CVE_RECORD", "dataVersion": "5.1"}

{}

{"affected": [{"affectedData": [{"product": "stunnel", "vendor": "n/a", "versions": [{"status": "affected", "version": "stunnel 5.57"}]}], "source": "secalert@redhat.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:stunnel:stunnel:*:*:*:*:*:*:*:*", "matchCriteriaId": "99F6A33C-E8E1-4C44-978D-6F475DB634E0", "versionEndExcluding": "5.57", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality."}, {"lang": "es", "value": "Se encontr\u00f3 un fallo en stunnel versiones anteriores a 5.57, donde comprueba inapropiadamente los certificados del cliente cuando est\u00e1 configurado para usar las opciones de redireccionamiento y verifyChain. Este fallo permite a un atacante con un certificado firmado por una Autoridad de Certificaci\u00f3n, que no es el aceptado por el servidor de stunnel, para acceder al servicio de t\u00fanel en lugar de ser redireccionado a la direcci\u00f3n especificada en la opci\u00f3n de redireccionamiento. La mayor amenaza de esta vulnerabilidad es la confidencialidad"}], "id": "CVE-2021-20230", "lastModified": "2026-06-17T03:33:30.657", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "MEDIUM", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "NONE", "baseScore": 5.0, "confidentialityImpact": "PARTIAL", "integrityImpact": "NONE", "vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N", "version": "2.0"}, "exploitabilityScore": 10.0, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2021-02-23T17:15:13.753", "references": [{"source": "secalert@redhat.com", "tags": ["Issue Tracking", "Third Party Advisory"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226"}, {"source": "secalert@redhat.com", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9"}, {"source": "secalert@redhat.com", "tags": ["Third Party Advisory"], "url": "https://security.gentoo.org/glsa/202105-02"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Issue Tracking", "Third Party Advisory"], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Third Party Advisory"], "url": "https://github.com/mtrojnar/stunnel/commit/ebad9ddc4efb2635f37174c9d800d06206f1edf9"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Third Party Advisory"], "url": "https://security.gentoo.org/glsa/202105-02"}], "sourceIdentifier": "secalert@redhat.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}], "source": "secalert@redhat.com", "type": "Secondary"}]}

{"affected_release": [{"advisory": "RHSA-2021:0618", "cpe": "cpe:/o:redhat:enterprise_linux:8", "package": "stunnel-0:5.56-5.el8_3", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2021-02-22T00:00:00Z"}, {"advisory": "RHSA-2021:0620", "cpe": "cpe:/o:redhat:rhel_eus:8.1", "package": "stunnel-0:5.48-6.el8_1", "product_name": "Red Hat Enterprise Linux 8.1 Extended Update Support", "release_date": "2021-02-22T00:00:00Z"}, {"advisory": "RHSA-2021:0619", "cpe": "cpe:/o:redhat:rhel_eus:8.2", "package": "stunnel-0:5.48-6.el8_2", "product_name": "Red Hat Enterprise Linux 8.2 Extended Update Support", "release_date": "2021-02-22T00:00:00Z"}], "bugzilla": {"description": "stunnel: client certificate not correctly verified when redirect and verifyChain options are used", "id": "1925226", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1925226"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "status": "verified"}, "cwe": "CWE-295", "details": ["A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality.", "A flaw was found in stunnel, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality."], "name": "CVE-2021-20230", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:5", "fix_state": "Not affected", "package_name": "stunnel", "product_name": "Red Hat Enterprise Linux 5"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "stunnel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "stunnel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "stunnel", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2020-10-11T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-20230\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-20230"], "statement": "This issue did not affect the versions of stunnel as shipped with Red Hat Enterprise Linux 5, 6, and 7 as they did not include support for the \"redirect\" option.", "threat_severity": "Important"}

{}