PT-2026-38282 · Grav · Grav+1

Published 2026-05-06 · Updated 2026-05-19 · CVE-2026-42844

Positive Technologies (AI Summary)

CVSS v3.1

8.8

High

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Grav version 2.0.0-beta.2

Description A low-privileged authenticated API user with api.media.write permissions can achieve full administrative compromise of the Grav API. The issue exists in the API plugin's blueprint upload flow because the endpoint "/api/v1/blueprint-upload" accepts caller-controlled destination and scope values to resolve the filesystem write target. By using destination=self@: and scope=users/anything, an attacker can write an arbitrary YAML file into the user/accounts/ directory. Since the system accepts account YAML files and supports plaintext passwords on first login, this allows the creation of a new account with api.super privileges, leading to vertical privilege escalation.

Recommendations Update the API to version 1.0.0-beta.17. As a temporary workaround, restrict access to the "/api/v1/blueprint-upload" endpoint or disable the api.media.write permission for untrusted users.

Exploit

Fix

Improper Privilege Management

Unrestricted File Upload

Weakness Enumeration

CWE-269

CWE-434

Related Identifiers

CVE-2026-42844

GHSA-6XX2-M8WV-756H

Affected Products

Api

Grav

References · 8

• 🔥 https://github.com/getgrav/grav/security/advisories/GHSA-6xx2-m8wv-756h · Exploit
• https://osv.dev/vulnerability/GHSA-6xx2-m8wv-756h · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-42844 · Security Note
• https://github.com/getgrav/grav · Note
• https://github.com/getgrav/grav-plugin-api/commit/97fc02844a35f743dfe93d34efd92d47eedd5bc5 · Note
• https://t.me/cveNotify/164111 · Telegram Post
• https://t.me/CVEtracker/53546 · Telegram Post
• https://twitter.com/CVEnew/status/2054323971571785733 · Twitter Post