CVE-2026-54894
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
Allocation of Resources Without Limits or Throttling in guardian (versions from 0.1.0 before 2.4.1) allows denial of service via unbounded atom creation from attacker-influenced binary input.
Risk Assessment
An attacker can exhaust the BEAM atom table, crashing the node and taking down all applications running on it.
Recommendation
Update guardian to version 2.4.1 or later.
Other vulnerabilities in guardian
See all- CVE-2026-34116Critical
A vulnerability in the Guardian language system allows an unauthenticated remote attacker to execute arbitrary OS commands by injecting shell metacharacters into the 'id' parameter in transcribe.php. The parameter is passed directly to the PHP exec() function without any sanitization.
- CVE-2026-34114Critical
The vulnerability in the Guardian language system involves passing the 'id' GET parameter directly into a PHP exec() call in translate_text.php without sanitization. No authentication is required, allowing an unauthenticated remote attacker to execute arbitrary OS commands.
- CVE-2026-34113Critical
A vulnerability in the Guardian language-system allows an unauthenticated attacker to execute arbitrary OS commands remotely by injecting shell metacharacters into the id parameter in speech_text.php.
- CVE-2026-34109Critical
A vulnerability in the Guardian language system allows an unauthenticated attacker to execute arbitrary OS commands remotely by injecting shell metacharacters into the 'id' GET parameter passed directly to the PHP exec() function in speech.php.
- CVE-2026-34108Critical
A vulnerability in the Guardian language-system allows an unauthenticated remote attacker to execute arbitrary OS commands by injecting shell metacharacters into the id parameter, which is passed unsanitized to the exec() function in text.php.
- CVE-2026-34106Critical
A vulnerability in the Guardian language system allows an unauthenticated attacker to execute arbitrary OS commands remotely by injecting shell metacharacters into the 'id' parameter in subtitles.php. The parameter is passed directly to the PHP exec() function without any sanitization.
- CVE-2026-55735High
Improper Verification of Cryptographic Signature in guardian (versions from 1.0.0 before 2.4.1) allows an unauthenticated attacker to revoke a victim's session with a forged JWT token.
- CVE-2026-55734High
A vulnerability in the Guardian library (Guardian.Permissions module) allows a denial of service attack via BEAM atom-table exhaustion. The encode_permissions!/1 function converts map keys to atoms without validation, and atoms are never garbage collected, exhausting the fixed-size atom table.
- CVE-2026-55733High
A vulnerability in the Guardian library (Elixir) allows DoS via unbounded atom creation from attacker-controlled binary input. The encode/3 function in Guardian.Permissions.AtomEncoding calls String.to_atom/1 without validation, exhausting the BEAM atom table and crashing the node.
Original NVD description (English source)
Allocation of Resources Without Limits or Throttling in ueberauth guardian allows denial of service via unbounded atom creation from attacker-influenced binary input. Guardian.Plug.Keys derives connection and session namespace keys by passing arbitrary binaries to String.to_atom/1. base_key/1 in lib/guardian/plug/keys.ex converts any binary into the atom :"guardian_<input>", and the derived helpers claims_key/1, resource_key/1, and token_key/1 create a second atom on top of that. key_from_other/1 likewise converts a regex-captured binary through String.to_atom/1. The public specs advertise String.t() as a valid argument, so passing a string is documented usage, and higher-level entry points such as Guardian.Plug.current_token(conn, key: key) thread the caller-supplied key straight into these functions. String.to_atom/1 creates a brand-new atom for every previously unseen binary, atoms are never garbage collected, and the BEAM atom table is fixed at roughly 1,048,576 entries by default. An application that routes attacker-influenced data (a tenant identifier, header, or other request input) into a Guardian key therefore mints one permanent atom per distinct value. A modest stream of varied, unauthenticated input permanently consumes the atom table and crashes the BEAM node, taking down every application running on it. This issue affects guardian: from 0.1.0 before 2.4.1.