{"answers":{"affected":"1 open source package ship an affected version, including guardian. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55734 exists.","fix":"Upgrade guardian to 2.4.1 or later.","what":"CVE-2026-55734 is a medium-severity denial of service vulnerability in ueberauth guardian, published on 1 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-55734 and fix it if it is affected.\n\nWhat it is: CVE-2026-55734 is a medium-severity denial of service vulnerability in ueberauth guardian, published on 1 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55734 exists.\n\nAffected packages and fixed versions:\n- guardian (Hex): affected from 2.0.0; fixed in 2.4.1\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-55734/ (Markdown: https://insights.sbomify.com/CVE-2026-55734/index.md)","id":"CVE-2026-55734","markdown":"https://insights.sbomify.com/CVE-2026-55734/index.md","name":"CVE-2026-55734","record":{"aliases":["EEF-CVE-2026-55734","GHSA-9qx2-v587-q3gg"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Elixir Guardian library","requires_auth":"none","summary":"An attacker can crash the BEAM node by exhausting the atom table via unvalidated keys in permission maps, affecting Elixir Guardian library users.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[{"product":"guardian","vendor":"ueberauth"}],"cvss":{"score":6.9,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H","version":"4.0"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"}],"description":"Allocation of Resources Without Limits or Throttling vulnerability in ueberauth guardian (Guardian.Permissions module) allows a denial of service via BEAM atom-table exhaustion.\n\nThis vulnerability is associated with program file lib/guardian/permissions.ex and program routines 'Elixir.Guardian.Permissions':encode_permissions!/1, 'Elixir.Guardian.Permissions':encode_permissions_into_claims!/2, 'Elixir.Guardian.Permissions':do_encode_permissions!/2.\n\nThe Guardian.Permissions mixin installs a public encode_permissions!/1 function on every module that does use Guardian.Permissions. For each key of the supplied map, encode_permissions!/1 calls String.to_atom(to_string(k)) before any validation runs. The integer-value clause of do_encode_permissions!/2 then short-circuits straight to encoding without validating the key against the configured permission set, so a key with an integer value is interned as a fresh atom with no exception raised. Atoms are never garbage collected and the BEAM atom table is a fixed-size resource (default roughly 1,048,576 entries), so each unique attacker-chosen key permanently consumes one slot. An attacker who can influence a permission map that reaches encode_permissions!/1 (for example a permissions map read from a request body and passed into token issuance via encode_permissions_into_claims!/2) can mint an unbounded number of atoms and exhaust the atom table, crashing the entire BEAM node and every service running on it. The sibling decode_permissions/1 is not affected because it skips keys absent from the configured permission set.\n\nThis issue affects guardian: from 2.0.0 before 2.4.1.","ecosystems":["Hex"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"guardian atom exhaustion in Guardian.Permissions.encode_permissions!/1","id":"CVE-2026-55734","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":1,"n_references":4,"next":{"headline":"Guardian.revoke/3 acts on unverified token claims, allowing forged-token session revocation","id":"CVE-2026-55735"},"packages":[{"ecosystem":"Hex","fixed":["2.4.1"],"introduced":["2.0.0"],"last_affected":[],"package":"guardian","purl":"pkg:hex/guardian","source":"EEF-CVE-2026-55734"}],"prev":{"headline":"Atom-table exhaustion denial of service in Guardian permissions AtomEncoding via unbounded atom creation","id":"CVE-2026-55733"},"products":["guardian"],"published":"2026-08-01","related":[{"cvss_score":8.2,"headline":"Guardian.revoke/3 acts on unverified token claims, allowing forged-token session revocation","id":"CVE-2026-55735","kev_date_added":null,"published":"2026-08-01"},{"cvss_score":6.9,"headline":"Atom-table exhaustion denial of service in Guardian via unbounded atom creation from binary keys","id":"CVE-2026-54894","kev_date_added":null,"published":"2026-08-01"},{"cvss_score":6.9,"headline":"Atom-table exhaustion denial of service in Guardian permissions AtomEncoding via unbounded atom creation","id":"CVE-2026-55733","kev_date_added":null,"published":"2026-08-01"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Erlang Ecosystem Foundation","prefix":"EEF"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-03","vendors":["ueberauth"]},"summary":"An attacker can crash the BEAM node by exhausting the atom table via unvalidated keys in permission maps, affecting Elixir Guardian library users.","url":"https://insights.sbomify.com/CVE-2026-55734/"}