{"cve":{"cve_id":"CVE-2026-55737","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00288,"epss_percentile":0.19946,"epss_as_of":"2026-10-15","description":"Signed to Unsigned Conversion Error and Out-of-bounds Write vulnerability in Erlang OTP erts allows an attacker who can supply a crafted Erlang external term format (ETF) binary to binary_to_term/1 to corrupt the BEAM heap pointer and crash the virtual machine.\n\nWhen decoding a LARGE_TUPLE_EXT term, the validation pass decoded_size() in erts/emulator/beam/external.c reads the 32-bit arity field as unsigned (get_uint32()), while the decode pass dec_term() reads the same field as a signed 32-bit integer (get_int32()) into an int. An arity wire value of 0x80000000 passes validation as 2147483648 but decodes as -2147483648, so the subsequent hp += n moves the heap allocation pointer backward. Neither pass enforces the runtime tuple-arity limit MAX_ARITYVAL. The result is an out-of-bounds heap write; in practice the VM detects an impossible heap size and aborts, denying service. The required padding is large when uncompressed but the compressed-ETF envelope shrinks it to a small payload on the wire.\n\nThis issue affects OTP from OTP 25.0 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to erts from 13.0 before 17.0.4, 16.4.0.4 and 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Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":"4.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"L","value_label":"Local"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"AT","name":"Attack Requirements","value":"N","value_label":"None"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"N","value_label":"None"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"N","value_label":"None"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"SC","name":"Confidentiality (Subsequent System)","value":"N","value_label":"None"},{"metric":"SI","name":"Integrity (Subsequent System)","value":"N","value_label":"None"},{"metric":"SA","name":"Availability (Subsequent System)","value":"N","value_label":"None"}]},"affected":[{"vendor_slug":"erlang","vendor_name":"erlang","product_slug":"erlang-otp","product_name":"erlang/otp","version_start":null,"version_start_inclusive":null,"version_end":null,"version_end_inclusive":null,"cpe23_uri":"cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"},{"vendor_slug":"erlang","vendor_name":"erlang","product_slug":"erts","product_name":"erts","version_start":"13.0","version_start_inclusive":true,"version_end":"15.2.7.11","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:a:erlang:erts:*:*:*:*:*:*:*:*"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/erlang/otp/security/advisories/GHSA-446w-268v-9462","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://cna.erlef.org/cves/CVE-2026-55737.html","source_type":"MISC","tags":[]},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-55737","source_type":"MISC","tags":[]},{"url":"https://www.erlang.org/doc/system/versions.html#order-of-versions","source_type":"MISC","tags":[]},{"url":"https://github.com/erlang/otp/commit/c5210b42a9d3d96f3d25601942ce8122be0f3761","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-07-27T15:13:54.699000Z","label":"CVE 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