0.0
NA
CVE-2026-49858
API Platform Core: Cross-user attribute leak in JSON:API and HAL item normalizers due to missing isCacheKeySafe gate
Description

API Platform Core is a system to create hypermedia-driven REST and GraphQL APIs. In versions from 2.6.0 prior to 4.1.29, 4.2.26, and 4.3.12, a missing isCacheKeySafe gate in the JSON:API and HAL item normalizers causes a cross-user attribute leak. #[ApiProperty(security: ...)] is evaluated per request to decide whether a property is exposed. The componentsCache arrays in ApiPlatform\JsonApi\Serializer\ItemNormalizer and ApiPlatform\Hal\Serializer\ItemNormalizer are keyed on $context['cache_key'], which is set unconditionally before delegating to the parent normalizer. The component structure (attributes, relationships, links) computed for one request can therefore be reused for a subsequent request whose user has a different set of accessible properties. A user with lower privileges may end up seeing the structure of properties that the security predicate would otherwise have hidden for them. This issue has been fixed in versions 4.1.29, 4.2.26, and 4.3.12.

INFO

Published Date :

July 1, 2026, 7:24 p.m.

Last Modified :

July 1, 2026, 7:24 p.m.

Remotely Exploit :

No

Source :

GitHub_M
Affected Products

The following products are affected by CVE-2026-49858 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Api-platform core
Solution
Update API Platform Core to patch versions to fix cross-user attribute leak.
  • Update API Platform Core to 4.1.29 or later.
  • Update API Platform Core to 4.2.26 or later.
  • Update API Platform Core to 4.3.12 or later.

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