Cyber Resilience

CVE-2026-42609

Access Control in Getgrav Grav ≤ 1.8.0

Public PoCAccess Control
Published
11 May 2026
Modified
17 June 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS Score 0.0046 38th percentile
Risk Priority 60 floored blend · peak EPSS

Summary

CVE-2026-42609 is a high-severity Improper Privilege Management (CWE-269) vulnerability in Getgrav Grav. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Abuse Elevation Control Mechanism (T1548); ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-2 (Account Management) and AC-24 (Access Control Decisions) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access ControlA06:2025 Insecure Design

EU & UK References

Vulnerability Data

Grav is a file-based Web platform. Prior to 2.0.0-beta.2, a business logic vulnerability in the Grav Admin Panel allows a low-privileged user (with only user creation permissions) to overwrite existing accounts, including the primary administrator. By creating a new user…

more

with a username that already exists, the system updates the existing account's metadata and permissions instead of rejecting the request. This leads to a Denial of Service (DoS) on administrative functions and Privilege De-escalation of the root account. This vulnerability is fixed in 2.0.0-beta.2.

CWE(s)
CWE-269CWE-285CWE-639CWE-837

Related Threats

MITRE ATT&CK Enterprise Techniques

T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
attack.mitre.org →
T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1548.001 Setuid and Setgid Privilege Escalation
An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context.
attack.mitre.org →
T1548.002 Bypass User Account Control Privilege Escalation
Adversaries may bypass UAC mechanisms to elevate process privileges on system.
attack.mitre.org →
T1548.003 Sudo and Sudo Caching Privilege Escalation
Adversaries may perform sudo caching and/or use the sudoers file to elevate privileges.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-66301Same product: Getgrav Grav
CVE-2024-34082Same product: Getgrav Grav
CVE-2026-42844Same product: Getgrav Grav
CVE-2025-66306Same product: Getgrav Grav
CVE-2023-21549Shared CWE-269, CWE-285
CVE-2026-47744Shared CWE-269, CWE-285
CVE-2026-33074Shared CWE-269, CWE-285
CVE-2026-50201Shared CWE-269, CWE-285
CVE-2026-31836Shared CWE-269, CWE-285
CVE-2026-27803Shared CWE-269, CWE-285

Affected Assets

getgrav
grav
2.0.0 · ≤ 1.8.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 11 hardening rules · 8 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.3.3
  • V6.5.1
  • V7.6.2
  • V17.3.1

Mitigating Controls (NIST 800-53 r5) AI

AC-24 Access Control Decisions good match

Mandates that access-control decisions are made and applied to each request before access occurs.

AC-25 Reference Monitor good match

Requires a tamperproof, always-invoked reference monitor that performs authorization checks.

AC-3 Access Enforcement good match

Directly requires enforcement of approved authorizations for every access request, stopping improper or missing checks.

AC-2 Account Management good match

Account management directly governs assignment and tracking of privileges so proper implementation stops the weakness from being introduced.

AC-5 Separation of Duties good match

Separation of duties constrains how privileges may be assigned, reducing the chance of overly broad actor control.

AC-6 Least Privilege good match

Least privilege is the direct countermeasure to improper privilege management; implementing it eliminates the root cause.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 full match
prevents

Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.

PR.IR-01 mostly match
prevents

Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.

PR.PS-06 mostly match
prevents

Secure SDLC practices catch and eliminate most authorization defects before release, yet a single broad outcome cannot address every design, role, and runtime facet of CWE-285.

PR.AA-01 partial match
prevents

PR.AA-01 supplies credential/identity lifecycle support that can reduce some privilege-assignment errors but does not itself assign, modify, or check privileges, leaving most of CWE-269's risk unaddressed.

PR.PS-01 partial match
prevents

Config baselines and default reviews can enforce some privilege-related settings (one facet) but do not address code-level assignment/tracking logic that defines CWE-269.

PR.PS-05 partial match
prevents

PR.PS-05 can partially limit exploitability of some privilege issues via execution restrictions, but does not address the core design/implementation flaws of CWE-269 at all.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.18 Access rights mostly match
prevents

Requiring owner approval, segregation of duties, and periodic reviews prevents the assignment of excessive or unnecessary privileges to users or processes.

A.8.2 Privileged access rights mostly match
prevents

Enforcing minimum-necessary privileges, temporary grants, and separation of administrative versus normal identities prevents the over-assignment of rights that CWE-269 describes.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect missing authorization checks but does not prevent the weakness in production.

A.8.3 Information access restriction mostly match
prevents

Dynamic techniques that grant the minimum necessary rights for a given time window and revoke them afterward reduce the window in which excessive or unnecessary privileges can be exploited.

A.5.1 Policies for information security partial match
prevents

By requiring documented authorization rules and periodic policy reviews, the control makes it less likely that authorization decisions will be omitted or implemented inconsistently across applications.

A.5.15 Access control partial match
prevents

Explicit restrictions on privileged access and segregation of duties limit the scope of privileges that can be assigned, reducing the chance that excessive or unnecessary privileges are granted to entities.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-252656 The OL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-285
  • V-248581 OL 8 must require users to provide a password for privilege escalation. prevents CWE-285
RHEL 7 (3 rules)
  • V-204429 The Red Hat Enterprise Linux operating system must be configured so that users must provide a password for privilege escalation. prevents CWE-285
  • V-204430 The Red Hat Enterprise Linux operating system must be configured so that users must re-authenticate for privilege escalation. prevents CWE-285
  • V-251704 The Red Hat Enterprise Linux operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-285
RHEL 8 (1 rule)
  • V-251712 The RHEL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-285
Windows 10 (1 rule)
  • V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows 11 (1 rule)
  • V-253269 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows Server 2016 (1 rule)
  • V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-269
Windows Server 2019 (1 rule)
  • V-205746 Windows Server 2019 must only allow Administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269
Windows Server 2022 (1 rule)
  • V-254428 Windows Server 2022 must only allow administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269

References