{"id":"CVE-2026-115693","revision":"e0792a264e0e4fdfb448b73d9269e824","records":[{"revision":"e0792a264e0e4fdfb448b73d9269e824","observedAt":"2026-10-26T15:35:30.984+00:00","statement":{"source":"cve-program","id":"CVE-2026-115693","aliases":[],"title":"Custom cacerts or cacertfile do not restrict trust to the pinned CA in hackney","description":"Improper Certificate Validation vulnerability in hackney_ssl in benoitc hackney allows an on-path attacker to impersonate a server pinned to a private certificate authority via a certificate chain that ends in a publicly trusted root. hackney adds {partial_chain, fun hackney_ssl:partial_chain/1} to every verify_peer configuration. The callback returns any certificate in the peer chain whose public key matches a root in the bundled certifi store as the trust anchor, and OTP honours that callback over the configured cacerts. hackney_ssl:merge_ssl_opts/3 kept the callback when the caller replaced the trust store with cacerts or cacertfile in ssl_options, so a connection pinned to a private CA still accepted any chain that carried a publicly trusted root.\n\nThe hostname check still applies, so the attacker needs a publicly trusted certificate for the pinned hostname.\n\nThis issue affects hackney: from 1.24.0 before 4.9.0.","state":0,"publishedAt":"2026-10-26T13:49:29.374+00:00","modifiedAt":"2026-10-26T13:49:29.374+00:00","affected":[{"ecosystem":"https://repo.hex.pm","name":"hackney","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"collectionURL\": \"https://repo.hex.pm\",\n                    \"cpes\": [\n                        \"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*\"\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"modules\": [\n                        \"hackney_ssl\"\n                    ],\n                    \"packageName\": \"hackney\",\n                    \"packageURL\": \"pkg:hex/hackney\",\n                    \"product\": \"hackney\",\n                    \"programFiles\": [\n                        \"src/hackney_ssl.erl\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"hackney_ssl:ssl_opts/2\"\n                        },\n                        {\n                            \"name\": \"hackney_ssl:merge_ssl_opts/3\"\n                        },\n                        {\n                            \"name\": \"hackney_ssl:partial_chain/1\"\n                        }\n                    ],\n                    \"repo\": \"https://github.com/benoitc/hackney\",\n                    \"vendor\": \"benoitc\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"4.9.0\",\n                            \"status\": \"affected\",\n                            \"version\": \"1.24.0\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"https://github.com","name":"benoitc/hackney","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"collectionURL\": \"https://github.com\",\n                    \"cpes\": [\n                        \"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*\"\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"modules\": [\n                        \"hackney_ssl\"\n                    ],\n                    \"packageName\": \"benoitc/hackney\",\n                    \"packageURL\": \"pkg:github/benoitc/hackney\",\n                    \"product\": \"hackney\",\n                    \"programFiles\": [\n                        \"src/hackney_ssl.erl\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"hackney_ssl:ssl_opts/2\"\n                        },\n                        {\n                            \"name\": \"hackney_ssl:merge_ssl_opts/3\"\n                        },\n                        {\n                            \"name\": \"hackney_ssl:partial_chain/1\"\n                        }\n                    ],\n                    \"repo\": \"https://github.com/benoitc/hackney\",\n                    \"vendor\": \"benoitc\",\n                    \"versions\": [\n                        {\n                            \"lessThan\": \"915eb5737e9c489d8fc22eec8cdae30e9b027be4\",\n                            \"status\": \"affected\",\n                            \"version\": \"d8a9afcf5c3849904274e2eba1df56c63d1a1a0c\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","score":9.1,"severity":"CRITICAL"}],"references":["https://github.com/benoitc/hackney/pull/978","https://cna.erlef.org/cves/CVE-2026-115693.html","https://osv.dev/vulnerability/EEF-CVE-2026-115693","https://github.com/benoitc/hackney/releases/tag/4.9.0","https://github.com/benoitc/hackney/commit/d8a9afcf5c3849904274e2eba1df56c63d1a1a0c","https://github.com/benoitc/hackney/commit/915eb5737e9c489d8fc22eec8cdae30e9b027be4"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-115693","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-115693","identifiers":["CVE-2026-115693"]},"retained":false,"historicalAffected":[]}],"coverage":[]}