CVE-2026-105270: Unbounded atom creation while parsing SAML messages in esaml allows atom table exhaustion
Description
Allocation of Resources Without Limits or Throttling vulnerability in esaml_binding in dropbox esaml allows an unauthenticated attacker to exhaust the Erlang VM atom table and crash the node via a crafted SAMLResponse. esaml_binding:decode_response/2 parses the decoded SAMLResponse with xmerl_scan:string/2, which interns every element name, attribute name, and namespace prefix it reads as a permanent atom. The SAML consume (ACS) and single-logout endpoints call it on unauthenticated requests before any signature check, so one well-formed document with thousands of distinct names mints thousands of atoms while staying inside the 128 KB request body limit. Atoms are never reclaimed and the VM caps the atom table at about one million entries, so a few dozen requests abort the node. This issue affects esaml: from 0.1.0 onward.
CWE-770
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
arekinath: esamldropbox: esamlhandnot2: esaml
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- cna.erlef.org/cves/CVE-2026-105270.html (opens in new tab)
- github.com/arekinath/esaml/commit/deeb84378d5c82153b470e99d24f77c38afca14a (opens in new tab)
- github.com/dropbox/esaml/commit/deeb84378d5c82153b470e99d24f77c38afca14a (opens in new tab)
- github.com/handnot2/esaml/commit/deeb84378d5c82153b470e99d24f77c38afca14a (opens in new tab)
- osv.dev/vulnerability/EEF-CVE-2026-105270 (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)