CVE-2026-86411

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{"acknowledgement": "Red Hat would like to thank Stanislav Fort (Aisle Research) for reporting this issue.", "bugzilla": {"description": "curl: curl: FTP connection reuse inherits client-certificate", "id": "2550364", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2550364"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N", "status": "draft"}, "cwe": "CWE-488", "details": ["A flaw was found in curl that can allow unauthorized access through improper session reuse. When an unencrypted File Transfer Protocol (FTP) transfer reuses a pooled connection previously authenticated with a client certificate and upgraded using Transport Layer Security (TLS), curl fails to perform a new handshake or authentication. As a result, the subsequent transfer operates under the prior session's identity, allowing it to perform operations on the remote server with unintended authorization."], "name": "CVE-2026-86411", "package_state": [{"cpe": "cpe:/a:redhat:confidential_compute_attestation:1", "fix_state": "Not affected", "package_name": "build-of-trustee/trustee-rhel9", "product_name": "Confidential Compute Attestation"}, {"cpe": "cpe:/a:redhat:confidential_compute_attestation:1", "fix_state": "Not affected", "package_name": "openshift-sandboxed-containers/osc-podvm-payload-rhel9", "product_name": "Confidential Compute Attestation"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "curl", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "igvm", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "rust", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "s390utils", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "snphost", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "trustee", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "curl", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "curl", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "curl", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "curl", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "rust", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "snphost", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "curl", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "rust", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:jboss_core_services:1", "fix_state": "Not affected", "package_name": "jbcs-httpd24-curl", "product_name": "Red Hat JBoss Core Services"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Not affected", "package_name": "foreman", "product_name": "Red Hat Satellite 6"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Fix deferred", "package_name": "openvox-agent", "product_name": "Red Hat Satellite 6"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Not affected", "package_name": "puppet-agent", "product_name": "Red Hat Satellite 6"}], "public_date": "2026-10-14T12:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-86411\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-86411"], "statement": "This vulnerability is rated as Low impact by Red Hat because triggering it requires an uncommon sequence of operations where a client application shares a connection pool across both certificate-authenticated FTP sessions and unauthenticated cleartext transfers. In typical enterprise environments, FTP transfers utilizing client certificate authentication are exceptionally rare, substantially constraining real-world attack scenarios. Consequently, exploitation is confined to custom applications specifically designed to reuse connection caches across transfers with mismatched security postures.", "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": null}], "enrichment": {"confidence": 80.0, "confidence_source": "inferred", "scores": [{"score": 80.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "product": "curl", "vendor": "curl"}], "created": "2026-10-17T02:00:07.713723+00:00", "updated": "2026-10-29T22:15:04.257076+00:00", "vendors": ["curl", "curl$PRODUCT$curl"]}