{"url":"http://public2.vulnerablecode.io/api/vulnerabilities/349238?format=json","vulnerability_id":"VCID-ph4w-4hud-mkck","summary":"An issue was discovered in Mbed TLS 3.x before 3.6.6. An out-of-bounds read vulnerability in mbedtls_ccm_finish() in library/ccm.c allows attackers to obtain adjacent CCM context data via invocation of the multipart CCM API with an oversized tag_len parameter. This is caused by missing validation of the tag_len parameter against the size of the internal 16-byte authentication buffer. The issue affects the public multipart CCM API in Mbed TLS 3.x, where mbedtls_ccm_finish() can be invoked directly by applications. In Mbed TLS 4.x versions prior to the fix, the same missing validation exists in the internal implementation; however, the function is not exposed as part of the public API. Exploitation requires application-level invocation of the multipart CCM API.","aliases":[{"alias":"CVE-2026-34876"}],"fixed_packages":[{"url":"http://public2.vulnerablecode.io/api/packages/930541?format=json","purl":"pkg:deb/debian/mbedtls@0?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@0%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/930542?format=json","purl":"pkg:deb/debian/mbedtls@2.16.9-0.1?distro=trixie","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-5bxk-rknm-zfhc"},{"vulnerability":"VCID-f1fz-b8b6-dfb8"},{"vulnerability":"VCID-gvkn-6e2m-dyez"},{"vulnerability":"VCID-k8w1-nrjy-wfbe"},{"vulnerability":"VCID-kchn-2wez-bbb2"},{"vulnerability":"VCID-pj6w-rufw-nqgd"},{"vulnerability":"VCID-vp4q-81cq-33cw"},{"vulnerability":"VCID-vs6q-c4ug-xfer"},{"vulnerability":"VCID-wsvw-6tmk-3kdj"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@2.16.9-0.1%3Fdistro=trixie"}],"affected_packages":[{"url":"http://public2.vulnerablecode.io/api/packages/930540?format=json","purl":"pkg:deb/debian/mbedtls@2.28.3-1?distro=trixie","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-4sbv-dqyv-6baw"},{"vulnerability":"VCID-5bxk-rknm-zfhc"},{"vulnerability":"VCID-7ppw-f9jy-k7ae"},{"vulnerability":"VCID-7v3a-5q44-cucz"},{"vulnerability":"VCID-98cg-wuhp-qudq"},{"vulnerability":"VCID-f1fz-b8b6-dfb8"},{"vulnerability":"VCID-gvkn-6e2m-dyez"},{"vulnerability":"VCID-jeen-6u3v-8qab"},{"vulnerability":"VCID-kchn-2wez-bbb2"},{"vulnerability":"VCID-ph4w-4hud-mkck"},{"vulnerability":"VCID-pj6w-rufw-nqgd"},{"vulnerability":"VCID-vp4q-81cq-33cw"},{"vulnerability":"VCID-vs6q-c4ug-xfer"},{"vulnerability":"VCID-wsvw-6tmk-3kdj"},{"vulnerability":"VCID-x8et-cun9-6kgz"},{"vulnerability":"VCID-zpq1-dwvf-8ka2"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@2.28.3-1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/1026157?format=json","purl":"pkg:deb/debian/mbedtls@2.28.3-1","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-4sbv-dqyv-6baw"},{"vulnerability":"VCID-5bxk-rknm-zfhc"},{"vulnerability":"VCID-7ppw-f9jy-k7ae"},{"vulnerability":"VCID-7v3a-5q44-cucz"},{"vulnerability":"VCID-98cg-wuhp-qudq"},{"vulnerability":"VCID-f1fz-b8b6-dfb8"},{"vulnerability":"VCID-gvkn-6e2m-dyez"},{"vulnerability":"VCID-jeen-6u3v-8qab"},{"vulnerability":"VCID-kchn-2wez-bbb2"},{"vulnerability":"VCID-ph4w-4hud-mkck"},{"vulnerability":"VCID-pj6w-rufw-nqgd"},{"vulnerability":"VCID-vp4q-81cq-33cw"},{"vulnerability":"VCID-vs6q-c4ug-xfer"},{"vulnerability":"VCID-wsvw-6tmk-3kdj"},{"vulnerability":"VCID-x8et-cun9-6kgz"},{"vulnerability":"VCID-zpq1-dwvf-8ka2"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@2.28.3-1"},{"url":"http://public2.vulnerablecode.io/api/packages/930544?format=json","purl":"pkg:deb/debian/mbedtls@3.6.5-0.1~deb13u1?distro=trixie","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-4sbv-dqyv-6baw"},{"vulnerability":"VCID-jeen-6u3v-8qab"},{"vulnerability":"VCID-ph4w-4hud-mkck"},{"vulnerability":"VCID-x8et-cun9-6kgz"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@3.6.5-0.1~deb13u1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/1026158?format=json","purl":"pkg:deb/debian/mbedtls@3.6.5-0.1~deb13u1","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-4sbv-dqyv-6baw"},{"vulnerability":"VCID-jeen-6u3v-8qab"},{"vulnerability":"VCID-ph4w-4hud-mkck"},{"vulnerability":"VCID-x8et-cun9-6kgz"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@3.6.5-0.1~deb13u1"},{"url":"http://public2.vulnerablecode.io/api/packages/930543?format=json","purl":"pkg:deb/debian/mbedtls@3.6.5-0.1?distro=trixie","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-4sbv-dqyv-6baw"},{"vulnerability":"VCID-jeen-6u3v-8qab"},{"vulnerability":"VCID-ph4w-4hud-mkck"},{"vulnerability":"VCID-x8et-cun9-6kgz"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@3.6.5-0.1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/1056756?format=json","purl":"pkg:deb/debian/mbedtls@3.6.5-0.1","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-4sbv-dqyv-6baw"},{"vulnerability":"VCID-jeen-6u3v-8qab"},{"vulnerability":"VCID-ph4w-4hud-mkck"},{"vulnerability":"VCID-x8et-cun9-6kgz"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/mbedtls@3.6.5-0.1"}],"references":[{"reference_url":"https://api.first.org/data/v1/epss?cve=CVE-2026-34876","reference_id":"","reference_type":"","scores":[{"value":"0.00015","scoring_system":"epss","scoring_elements":"0.03384","published_at":"2026-04-07T12:55:00Z"},{"value":"0.00017","scoring_system":"epss","scoring_elements":"0.03993","published_at":"2026-04-04T12:55:00Z"},{"value":"0.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