CVE-2021-44878
mediumpriority · track · 30EPSS 0.009 · 59 %ileDEEUUSEPSS · scored 2026-10-27
If an OpenID Connect provider supports the "none" algorithm (i.e., tokens with no signature), pac4j v5.3.0 (and prior) does not refuse it without an explicit configuration on its side or for the "idtoken" response type which is not secure and violates the OpenID Core Specification. The "none" algorithm does not require any signature verification when validating the ID tokens, which allows the attacker to bypass the token validation by injecting a malformed ID token using "none" as the value of "alg" key in the header with an empty signature value.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
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affected products (9)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2024-0794Dell ECS: Mehrere SchwachstellenDeutsch2024-04-04csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell ECS ausnutzen, um seine Privilegien zu erweitern, beliebigen Programmcode mit Administratorrechten auszuführen, Informationen offenzulegen, Dateien zu manipulieren, einen Cross-Site-Scripting-Angriff durchzuführen, Sicherheitsvorkehrungen zu umgehen oder einen Denial of Service Zustand herbeizuführen.
- GHSA-xhw6-hjc9-679mPac4j token validation bypass if OpenID Connect provider supports none algorithm2022-01-08ghsa · osvUS
If an OpenID Connect provider supports the “none” algorithm (i.e., tokens with no signature), pac4j v5.3.0 (and prior) does not refuse it without an explicit configuration on its side or for the “idtoken” response type which is not secure and violates the OpenID Core Specification. The "none" algorithm does not require any signature verification when validating the ID tokens, which allows the attacker to bypass the token validation by injecting a malformed ID token using "none" as the value of "alg" key in the header with an empty signature value.
also known as (3)
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sources
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references (10)
External citations — patches, advisories, analysis.
- https://github.com/pac4j/pac4j/commit/22b82ffd702a132d9f09da60362fc6264fc281aecnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-44878cnnvd
- https://openid.net/specs/openid-connect-core-1_0.html#IDTokencnnvd
- https://www.pac4j.org/blog/cve_2021_44878_is_this_serious.htmlcnnvd
- https://github.com/pac4j/pac4j/commit/22b82ffd702a132d9f09da60362fc6264fc281aeenisa_euvd
- https://openid.net/specs/openid-connect-core-1_0.html#IDTokenenisa_euvd
- https://www.pac4j.org/blog/cve_2021_44878_is_this_serious.htmlenisa_euvd
- https://github.com/pac4j/pac4j/commit/22b82ffd702a132d9f09da60362fc6264fc281aePatchThird Party Advisorynvd
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