High severity · published Oct 22, 2026
CVE-2026-105270
Unbounded atom creation while parsing SAML messages in esaml allows atom table exhaustion
New
8.7
CVSS
0.3%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ES
esaml · arekinath
deeb84378d5c82153b470e99d24f77c38afca14a · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105270
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105270
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-105270.html
github.com
https://github.com/arekinath/esaml/commit/deeb84378d5c82153b470e99d24f77c38afca14a
github.com
https://github.com/dropbox/esaml/commit/deeb84378d5c82153b470e99d24f77c38afca14a
github.com
https://github.com/handnot2/esaml/commit/deeb84378d5c82153b470e99d24f77c38afca14a
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-105270
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