CVE Catalog

CVE-2026-82760

HighCVSS 8.2
Published: Translated: NVD NIST

Summary

An inefficient algorithmic complexity vulnerability in AshAuthentication allows an unauthenticated attacker to exhaust CPU and memory via an oversized base62 segment in an API key. The decoding functions have quadratic/cubic complexity and do not limit input length.

Risk Assessment

An attacker can cause denial of service by overloading CPU and memory.

Recommendation

Upgrade ash_authentication to version 4.15.0 or later (for 4.x) and 5.0.0-rc.14 or later (for 5.0.0-rc) which include the fix. Limit API key length.

Other vulnerabilities in AshAuthentication

See all
Original NVD description (English source)

Inefficient Algorithmic Complexity vulnerability in team-alembic AshAuthentication allows an unauthenticated attacker to exhaust CPU and memory via an oversized base62 segment in a submitted API key. AshAuthentication.Base.decode62/1 in lib/ash_authentication/base.ex splits its argument into one binary per character and folds it with charval62/2, which recomputes Integer.pow(62, index) at every position instead of accumulating by Horner's method, so cost grows roughly cubically in the input length. bindecode62/1 in the same module is quadratic through Integer.undigits/2 and Integer.digits/2. Neither function caps byte_size/1, and AshAuthentication.Strategy.ApiKey.SignInPreparation passes the underscore-separated segments of the submitted key straight into both, before any key lookup and without prior authentication. The surrounding rescue clauses catch exceptions, not CPU or memory exhaustion. This issue affects ash_authentication: from 4.8.0 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS