CVE-2026-75759
HighCVSS 7.6Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
The oidcc library (erlef) has an improper verification of cryptographic signature vulnerability. An unauthenticated attacker can impersonate an arbitrary user via an encrypted ID token or JARM response carrying no nested signature. The library accepts a JWE wrapping unsigned claims as fully validated, allowing minting tokens with arbitrary sub, iss, and aud without the provider's signing key.
Risk Assessment
An attacker can gain access to user accounts in systems using OpenID Connect, leading to confidentiality and integrity breaches. The vulnerability affects versions from 3.2.0-beta.1 before 3.9.0.
Recommendation
Update the oidcc library to version 3.9.0 or later, which includes the fix. Check for any compromised tokens.
Related vulnerabilities
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AJ-Report through 1.7.1 signs share tokens with a hard-coded JWT secret, allowing attackers to forge valid Share-Tokens offline. Attackers can mint a token with reportCode 'dataSet' to access the testTransform endpoint, which passes scripts to GroovyClassLoader for unauthenticated remote code execution.
- CVE-2026-120201Critical
Jpom 2.10.0 through 2.11.12 contains an authentication bypass vulnerability that allows unauthenticated attackers to gain super-administrator access by injecting query conditions into the JPOM-USER-TOKEN header. Attackers can send a value like 'is not null', which Hutool's Condition parser treats as an operator, then execute commands through Jpom's script features.
- CVE-2026-118235Critical
The SimpleForm plugin for WordPress (versions up to and including 3.10.2) is vulnerable to arbitrary file upload via the handle_upload function. Missing a server-side file key allowlist and pre-sanitization extension derivation allows a trailing-dot filename to bypass all extension and MIME validation, enabling unauthenticated attackers to upload executable files and achieve remote code execution. The only access control is a nonce printed into every public form's data-nonce attribute, trivially obtainable by any unauthenticated visitor.
- CVE-2026-103882Critical
The Acadlix LMS plugin for WordPress (versions up to and including 1.1.9) is vulnerable to arbitrary file deletion due to insufficient file path validation in the post_delete_assessment_file_by_id function. Authenticated attackers with subscriber-level access or higher can delete arbitrary files on the server, potentially leading to remote code execution when critical files such as wp-config.php are deleted. The route's permission callback only verifies a generic wp_rest nonce emitted in the public acadlixOptions JavaScript object on every frontend page, effectively reducing the authentication requirement to unauthenticated.
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The Uncanny Toolkit for LearnDash plugin for WordPress (up to 3.8.2) is vulnerable to Authentication Bypass via the 'email' parameter in uo_login_action(). A parser-differential flaw allows skipping account verification by using a raw string for lookup and a sanitized string for login. This lets unauthenticated attackers log in to unverified or suspended accounts if they know the credentials.
- CVE-2026-116512Critical
The Project Manager – AI Powered Project Management plugin for WordPress (up to 4.1.1) is vulnerable to Remote Code Execution via the 'id' parameter. The unsanitized value is concatenated into a validation rule string and then invoked as a dynamic PHP function without allowlist checks. This allows unauthenticated attackers to execute code on the server.
- CVE-2026-89270Critical
The Popup Builder plugin for WordPress in versions up to and including 4.4.5 does not properly verify that a user is authorized to perform an action. An unauthenticated attacker can trash all published popups on the site with a single GET request, amplified by a second flaw in SGPopup::find() that causes the trash branch to fire against every popup simultaneously.
- CVE-2026-116557Critical
The WP Booking System – Booking Calendar plugin for WordPress in versions up to and including 2.1.0.5 lacks a capability check in the wpbs_action_ajax_calendar_remove_note() function. An authenticated attacker with Subscriber-level access or above can delete arbitrary calendar notes belonging to any calendar.
- CVE-2026-109220Critical
The PDF Invoice for WooCommerce + Drag and Drop Template Builder plugin in versions up to and including 7.1.1 is vulnerable to PHP Object Injection via the 'customer_note' parameter. The checkout field is insufficiently sanitized and passed to unserialize() without validation, allowing unauthenticated attackers to execute code on the server.
- CVE-2026-117656Critical
The pow-auth Assent library's Sign in with Apple strategy trusts the browser-supplied 'user' parameter, which the client controls. That parameter is merged over the verified ID token claims, allowing an unauthenticated remote attacker to impersonate another user. Affects versions from 0.1.25 before 0.3.2.
Original NVD description (English source)
Improper Verification of Cryptographic Signature vulnerability in erlef oidcc allows an unauthenticated attacker to impersonate an arbitrary user via an encrypted ID token or JARM response carrying no nested signature. OpenID Connect Core 1.0 section 2 requires that an encrypted ID token be signed then encrypted, with the result being a Nested JWT, and JARM processing rule 5 requires the client to check the signature unconditionally. oidcc instead accepted a JWE wrapping unsigned claims as fully validated, so anyone holding the relying party's public encryption key could mint a token with an arbitrary sub, iss, and aud without possessing the provider's signing key. In oidcc_jwt_util:verify_decrypted_token/4, a decrypted payload that is not a signed JWS fell back to parsing the plaintext claims and returning them with no verifying key. oidcc_token:int_validate_jwt/4 then matched on the JOSE structure type rather than on whether a signature had been verified, and returned success. The JARM path in oidcc_token:validate_jarm/3 is reachable through the browser front channel. UserInfo responses are not affected, because OpenID Connect Core 1.0 section 5.3.2 permits them to be encrypted without also being signed. This issue affects oidcc: from 3.2.0-beta.1 before 3.9.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

