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
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 39th percentile
Risk Priority 60 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

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 39th 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)

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)

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.
T1574.005 Executable Installer File Permissions Weakness Stealth
Adversaries may execute their own malicious payloads by hijacking the binaries used by an installer.
T1574.010 Services File Permissions Weakness Stealth
Adversaries may execute their own malicious payloads by hijacking the binaries used by services.
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
T1012 Query Registry Discovery
Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-34082Same product: Getgrav Grav
CVE-2026-42844Same product: Getgrav Grav
CVE-2025-66306Same product: Getgrav Grav
CVE-2026-47744Shared CWE-269, CWE-285
CVE-2026-50201Shared CWE-269, CWE-285
CVE-2023-21549Shared CWE-269, CWE-285
CVE-2026-33074Shared CWE-269, CWE-285
CVE-2026-31836Shared CWE-269, CWE-285
CVE-2026-27803Shared CWE-269, CWE-285
CVE-2026-53515Shared 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)
  • 9 hardening rules · 6 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

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

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

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

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

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

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 mostly match
prevents

PR.AA-05 enforces least privilege/SoD and periodic reviews that directly remove most privilege-assignment defects, yet CWE-269 also covers escalation paths and role design outside a single access-management control.

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.IR-01 partial match
prevents

Network segmentation/zero-trust limits external reachability (partial prevention of exploitation) but leaves application-level authorization logic untouched, so the CWE remains fully introducible and only one facet of its risk is addressed.

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.

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.

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.

prevents

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

prevents

Defining and communicating authorization levels for each role limits the assignment of excessive or unnecessary privileges.

mitigates

Separating duties such as developing software from administering production systems prevents any one person from accumulating excessive privileges that would constitute improper privilege management.

finds

Independent reviewers evaluate whether authorization logic matches policy, thereby reducing the window in which incorrect or missing authorization checks remain in production.

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` (higher-evidence 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 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

References