{"id":34546,"date":"2026-01-07T17:47:16","date_gmt":"2026-01-07T17:47:16","guid":{"rendered":"http:\/\/localhost\/?p=34546"},"modified":"2026-01-07T17:47:16","modified_gmt":"2026-01-07T17:47:16","slug":"wolfssl-python-library-certrequired-mode-fails-to-enforce-client-certificate-requirement","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=34546","title":{"rendered":"wolfSSL Python library `CERT_REQUIRED` mode fails to enforce client certificate requirement_CVE-2025-15346"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A vulnerability in the handling of verify_mode = CERT_REQUIRED in the wolfssl Python package (wolfssl-py) causes client certificate requirements to not be fully enforced.\u00a0\\n\\nBecause the WOLFSSL_VERIFY_FAIL_IF_NO_PEER_CERT flag was not included, the behavior effectively matched CERT_OPTIONAL: a peer certificate was verified if presented, but connections were incorrectly authenticated when no client certificate was provided.\u00a0\\n\\nThis results in improper authentication, allowing attackers to bypass mutual TLS (mTLS) client authentication by omitting a client certificate during the TLS handshake.\u00a0\\n\\nThe issue affects versions up to and including 5.8.2.&#8221;,&#8221;published&#8221;:&#8221;2026-01-07T23:32:11.146Z&#8221;,&#8221;modified&#8221;:&#8221;2026-01-07T23:32:11.146Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;wolfSSL Python library `CERT_REQUIRED` mode fails to enforce client certificate requirement&#8221;,&#8221;source&#8221;:&#8221;wolfSSL&#8221;,&#8221;references&#8221;:&#8221;https:\/\/github.com\/wolfSSL\/wolfssl-py\/pull\/62\\nhttps:\/\/github.com\/wolfSSL\/wolfssl-py\/commit\/b4517dece79f682a8f453abce5cfc0b81bae769d\\nhttps:\/\/github.com\/wolfSSL\/wolfssl-py\/releases\/tag\/v5.8.4-stable&#8221;,&#8221;id&#8221;:&#8221;CVE-2025-15346&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-306&#8243;,&#8221;CWE-287&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;wolfSSL wolfSSL-py 5.3.0&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:9.3,&#8221;severity&#8221;:&#8221;CRITICAL&#8221;,&#8221;vector&#8221;:&#8221;CVSS:4.0\/AV:N\/AC:L\/AT:N\/PR:N\/UI:N\/VC:H\/VI:H\/VA:N\/SC:N\/SI:N\/SA:N\/AU:Y&#8221;,&#8221;version&#8221;:&#8221;4.0&#8243;},&#8221;cvss2&#8243;:{},&#8221;cvss3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;,&#8221;cvssV3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;}},&#8221;href&#8221;:&#8221;&#8221;,&#8221;category_name&#8221;:&#8221;CVE&#8221;,&#8221;post_link&#8221;:&#8221;&#8221;,&#8221;product&#8221;:&#8221;wolfSSL-py&#8221;,&#8221;version&#8221;:&#8221;5.3.0&#8243;,&#8221;vendor&#8221;:&#8221;wolfSSL&#8221;,&#8221;ai_description&#8221;:&#8221;Improper authentication due to incorrect handling of client certificate requirements in wolfSSL Python library&#8221;,&#8221;ai_severity&#8221;:&#8221;Critical&#8221;,&#8221;ai_vendor&#8221;:&#8221;wolfSSL&#8221;,&#8221;ai_product&#8221;:&#8221;wolfSSL-py&#8221;,&#8221;ai_version&#8221;:&#8221;up to 5.8.2&#8243;,&#8221;ai_score&#8221;:9.3}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A vulnerability in the handling of verify_mode = CERT_REQUIRED in the wolfssl Python package (wolfssl-py) causes client certificate requirements to not be fully enforced.\u00a0\\n\\nBecause the&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[9,6,8,55,12,13,7,11,5],"class_list":["post-34546","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-critical","tag-cve","tag-cvss","tag-cvss-93","tag-exploit","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - 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