CVE-2026-86696highCWE-770

CVE-2026-86696: high-severity vulnerability in arekinath esaml

Unbounded atom creation from unsigned LogoutResponse status codes in esaml allows atom table exhaustion

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.2epss 0.7%
Allocation of Resources Without Limits or Throttling vulnerability in esaml in dropbox esaml allows an unauthenticated attacker to exhaust the Erlang VM atom table and crash the node via unsigned LogoutResponse messages. esaml:status_code_map/1 in src/esaml.erl maps any StatusCode value it does not recognize to an atom with list_to_atom/1 on the last colon-separated segment of the URN. esaml_sp:validate_logout_response/2 verifies a signature only when the message carries one, so an unsigned LogoutResponse posted to the single-logout endpoint reaches esaml:decode_logout_response/1 and mints one permanent atom per distinct status value. Atoms are never reclaimed and the VM caps the atom table at about one million entries, so an attacker who posts that many distinct values aborts the node. This issue affects esaml: from 0.1.0 onward.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
arekinath · esamldropbox · esamlhandnot2 · esaml
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