CVE-2026-86696

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

No CVSS.

References

Link	Resource
https://cna.erlef.org/cves/CVE-2026-86696.html
https://github.com/arekinath/esaml/commit/be692b56245071899757afa7ef47e43593d3de96
https://github.com/dropbox/esaml/commit/be692b56245071899757afa7ef47e43593d3de96
https://github.com/handnot2/esaml/commit/be692b56245071899757afa7ef47e43593d3de96
https://osv.dev/vulnerability/EEF-CVE-2026-86696
https://cna.erlef.org/cves/CVE-2026-86696.html
https://osv.dev/vulnerability/EEF-CVE-2026-86696

Configurations

No configuration.

History

30 Oct 2026, 19:20

Type	Values Removed	Values Added
References	~~() https://cna.erlef.org/cves/CVE-2026-86696.html -~~	() https://cna.erlef.org/cves/CVE-2026-86696.html -
References	~~() https://osv.dev/vulnerability/EEF-CVE-2026-86696 -~~	() https://osv.dev/vulnerability/EEF-CVE-2026-86696 -

22 Oct 2026, 09:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 09:17

Updated : 2026-10-30 19:20

NVD link : CVE-2026-86696

Mitre link : CVE-2026-86696

CVE.ORG link : CVE-2026-86696

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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