Threats affecting pkg:generic/libucl

OAuthlib contains a vulnerability in its token grant handlers where an authenticated low-privilege client can supply a different client_id in the token request body, causing authorization checks to be performed under that other client identity. This affects the client_credentials and Resource Owner Password Credentials grant flows. The flaw arises because OAuthlib does not require the client_id in the request body to match the authenticated client's client_id before validating grant types and scopes. As a result, a low-privilege client can obtain tokens with scopes or grant types intended for a higher-privilege client if the application validator authorizes based on the client_id argument passed by OAuthlib. The vulnerability is fixed in version 2024.3.1_9.

pyasn1 versions up to 0.6.4 contain a denial of service vulnerability in the decoding of binary-encoded ASN.1 REAL values with large mantissas. The decoding process uses a quadratic-time algorithm that can cause high CPU usage and exhaustion when processing attacker-controlled input. This affects BER, CER, and DER decoders. The issue is fixed in pyasn1 version 0.6.5.

CVE-2026-119196 affects pyasn1 versions up to 0.6.4 and certain molecule versions, causing quadratic CPU consumption when decoding constructed BIT STRING values with many fragments. This can lead to CPU exhaustion and denial of service if attacker-controlled ASN.1 data is processed. The vulnerability arises from inefficient bit shifting during decoding in BER and CER decoders, and permissive DER schema-driven decoding. The issue is fixed in molecule version 3.0.5.

pyasn1 versions up to 0.6.4 have a quadratic-time denial of service vulnerability in decoding constructed OCTET STRINGs, character strings, and indefinite-length ANY types. The decoder repeatedly concatenates fragments inefficiently, causing CPU usage to grow quadratically with the number of fragments. This can lead to CPU exhaustion if attacker-controlled ASN.1 input is decoded without proper limits. The issue affects BER and CER decoding and certain non-conforming DER inputs. No confidentiality or integrity impact is reported.

CVE-2026-119194 is a vulnerability in the pyasn1 library (version 0.6.4) used by the molecule product, where schemaless decoding of BER, CER, or DER data with many distinct long tag IDs causes quadratic CPU usage. This can lead to excessive CPU consumption and reduced service availability when processing attacker-controlled inputs. The issue arises from inefficient handling of TagSet insertions during decoding. A fix is available in version 3.0.5.

joserfc version 0.21.1_3 up to but not including 0.23.1_2 has a vulnerability in its compact JWS size guard. The library calls bytes.split() on attacker-controlled input before validating segment sizes, causing it to allocate memory roughly equal to the payload size before rejecting it. This can lead to excessive memory allocation prior to size checks. A fix is available in version 0.23.1_2 that adds length checks before splitting the input.

The joserfc library's JWE General JSON decryption function accepts an unbounded recipients array, causing it to perform a costly RSA private-key decryption for every recipient without limit. This allows an unauthenticated attacker to cause CPU exhaustion (Denial of Service) by sending a single JWE JSON with many recipients. The library caps other structural elements but does not limit recipient count. The documented mitigation option does not reduce CPU usage. A fix is available in version 0.23.1_1.

CVE-2026-116672 is a vulnerability in Authlib's implementation of the OAuth 2.0 Dynamic Client Registration Management Protocol (RFC 7592). The provided example code for the ClientConfigurationEndpoint fails to enforce binding between the registration_access_token and the client being accessed, allowing an attacker with any valid token and knowledge of a client_id to bypass authorization and modify or delete client registrations. This flaw arises because the example implementations do not check that the token presented belongs to the client identified in the request. The issue affects versions >=0.11.11 and <0.23.1_2 of the mcp-atlassian product and is fixed in version 0.23.1_2.