{"id":"DEBIAN-CVE-2026-55737","details":"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.  When 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.  This 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 15.2.7.11.","modified":"2026-09-01T16:06:51.434717382Z","published":"2026-07-27T16:17:48.847Z","upstream":["CVE-2026-55737"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-55737"}],"affected":[{"package":{"name":"erlang","ecosystem":"Debian:12","purl":"pkg:deb/debian/erlang?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:25.2.3+dfsg-1","1:25.2.3+dfsg-1+deb12u1","1:25.2.3+dfsg-1+deb12u2","1:25.2.3+dfsg-1+deb12u3","1:25.2.3+dfsg-1+deb12u4","1:25.3.2.10+dfsg-1","1:25.3.2.10+dfsg-2","1:25.3.2.11+dfsg-1","1:25.3.2.12+dfsg-1","1:25.3.2.12+dfsg-2","1:25.3.2.12+dfsg-3","1:25.3.2.8+dfsg-1","1:26.0+dfsg-1","1:26.0.1+dfsg-1","1:26.0.2+dfsg-1","1:26.0~rc2+dfsg-1","1:26.0~rc3+dfsg-1","1:26.1.2+dfsg-1","1:26.2.1+dfsg-1","1:26.2.4+dfsg-1","1:27.0+dfsg-1","1:27.0.1+dfsg-1","1:27.0.1+dfsg-2","1:27.0.1+dfsg-3","1:27.0~rc3+dfsg-1","1:27.0~rc3+dfsg-2","1:27.0~rc3+dfsg-3","1:27.0~rc3+dfsg-4","1:27.1.2+dfsg-1","1:27.2+dfsg-1","1:27.2+dfsg-2","1:27.2+dfsg-3~exp1","1:27.2.1+dfsg-1","1:27.2.1+dfsg-2","1:27.2.2+dfsg-1","1:27.2.3+dfsg-1","1:27.2.4+dfsg-1","1:27.3+dfsg-1","1:27.3.1+dfsg-1","1:27.3.2+dfsg-1","1:27.3.3+dfsg-1","1:27.3.4+dfsg-1","1:27.3.4.1+dfsg-1","1:27.3.4.10+dfsg-1","1:27.3.4.11+dfsg-1","1:27.3.4.11+dfsg-2","1:27.3.4.11+dfsg-3","1:27.3.4.11+dfsg-4","1:27.3.4.11+dfsg-5","1:27.3.4.11+dfsg-6","1:27.3.4.11+dfsg-7","1:27.3.4.12+dfsg-1","1:27.3.4.3+dfsg-1","1:27.3.4.4+dfsg-1","1:27.3.4.6+dfsg-1","1:27.3.4.8+dfsg-1","1:27.3.4.9+dfsg-1","1:28.0+dfsg-1","1:28.0.1+dfsg-1","1:28.0.2+dfsg-1","1:28.0.4+dfsg-1","1:28.1.1+dfsg-1","1:28.2+dfsg-1","1:28.3+dfsg-1","1:28.3.1+dfsg-1","1:29.0+dfsg-1","1:29.0+dfsg-2","1:29.0.1+dfsg-1","1:29.0.2+dfsg-1","1:29.0.3+dfsg-1","1:29.0.4+dfsg-1","1:29.0~rc1+dfsg-1","1:29.0~rc1+dfsg-2","1:29.0~rc2+dfsg-1","1:29.0~rc3+dfsg-1","1:29.0~rc3+dfsg-2","1:29.0~rc3+dfsg-3","1:29.0~rc3+dfsg-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55737.json"}},{"package":{"name":"erlang","ecosystem":"Debian:13","purl":"pkg:deb/debian/erlang?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:27.3.4.1+dfsg-1+deb13u3"}]}],"versions":["1:27.3.4.1+dfsg-1","1:27.3.4.1+dfsg-1+deb13u1","1:27.3.4.1+dfsg-1+deb13u2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55737.json"}},{"package":{"name":"erlang","ecosystem":"Debian:14","purl":"pkg:deb/debian/erlang?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:29.0.4+dfsg-1"}]}],"versions":["1:27.3.4.1+dfsg-1","1:27.3.4.10+dfsg-1","1:27.3.4.11+dfsg-1","1:27.3.4.11+dfsg-2","1:27.3.4.11+dfsg-3","1:27.3.4.11+dfsg-4","1:27.3.4.11+dfsg-5","1:27.3.4.11+dfsg-6","1:27.3.4.11+dfsg-7","1:27.3.4.12+dfsg-1","1:27.3.4.3+dfsg-1","1:27.3.4.4+dfsg-1","1:27.3.4.6+dfsg-1","1:27.3.4.8+dfsg-1","1:27.3.4.9+dfsg-1","1:28.0+dfsg-1","1:28.0.1+dfsg-1","1:28.0.2+dfsg-1","1:28.0.4+dfsg-1","1:28.1.1+dfsg-1","1:28.2+dfsg-1","1:28.3+dfsg-1","1:28.3.1+dfsg-1","1:29.0+dfsg-1","1:29.0+dfsg-2","1:29.0.1+dfsg-1","1:29.0.2+dfsg-1","1:29.0.3+dfsg-1","1:29.0~rc1+dfsg-1","1:29.0~rc1+dfsg-2","1:29.0~rc2+dfsg-1","1:29.0~rc3+dfsg-1","1:29.0~rc3+dfsg-2","1:29.0~rc3+dfsg-3","1:29.0~rc3+dfsg-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55737.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}