Security readout for executives and security teams
Plain-English summary
CVE-2020-37256 affects Grav sites running versions before 1.6.30. A user who already has page-editing privileges in the Admin plugin can inject script into edited pages. If another user interacts with that content, the script may run in their browser, potentially enabling account abuse or malicious plugin installation.
Executive priority
Treat as a targeted CMS integrity risk, not an emergency unless untrusted editors exist. Prioritize patching public-facing Grav sites and sites with many content editors or delegated administrative access.
Technical view
This is a stored cross-site scripting issue in the Grav Admin plugin page editor default security configuration. It requires network access, low privileges, and user interaction. The CVSS 3.1 score is 5.4, with scope changed and limited confidentiality and integrity impact. Availability impact is not identified.
Likely exposure
Exposure is mainly Grav deployments below 1.6.30 that use the Admin plugin and allow users to edit pages. Risk increases where multiple editors or administrators share the same CMS environment.
Exploitation context
The provided sources do not report active exploitation, and the CVE is not listed as KEV. Exploitation requires an authenticated user with page-editing capability and a victim interaction path in the admin or rendered content context.
Researcher notes
Evidence supports a privileged stored XSS in Grav before 1.6.30. The bundle does not include proof-of-concept details, observed exploitation, or configuration-specific edge cases. Avoid assuming impact beyond the vendor-described ability to execute script and potentially install malicious plugins.
Mitigation direction
- Upgrade Grav to version 1.6.30 or later, following vendor guidance.
- Review which accounts have page-editing privileges and remove unnecessary access.
- Check Admin plugin and Grav security configuration against vendor recommendations.
- Review recent page edits for unexpected script-like content or unauthorized changes.
Validation and detection
- Inventory Grav versions across hosted sites and environments.
- Confirm whether the Admin plugin page editor is enabled and used.
- Identify users with page-editing privileges in each Grav instance.
- Verify patched instances are at Grav 1.6.30 or later.
- Review logs and content history for suspicious editor activity.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2020-37256 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N2.32.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
5.1MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
Base CVSS 3.1 score
5.4MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- GitHub Security Advisory (GHSA-cvmr-6428-87w9)CVE reference, VulnCheck · vendor-advisory
- VulnCheck Advisory: Grav - Cross-Site Scripting in Admin Plugin Page EditorCVE reference, VulnCheck · third-party-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.