Security readout for executives and security teams
Plain-English summary
CVE-2021-38243 is a critical remote code execution issue in xunruicms up to v4.5.1. An unauthenticated attacker could execute arbitrary code through a crafted GET request to /index.php, potentially taking over the web application or server context.
Executive priority
Prioritize within the emergency vulnerability queue for any exposed xunruicms deployment. The business risk is potential application takeover, data compromise, service disruption, and lateral movement from a public web server.
Technical view
The CVE describes CWE-94 improper control of code generation in /index.php, reachable over the network with low complexity and no privileges or user interaction. The CVSS v3.1 score is 9.8 with high confidentiality, integrity, and availability impact. Normalized affected vendor/product and CPE data are not provided.
Likely exposure
Organizations running xunruicms version 4.5.1 or earlier are the stated exposure group. Risk is highest where the application and /index.php are internet-facing. Source metadata does not provide CPEs, package names, hosting patterns, or a definitive fixed version.
Exploitation context
The CVE references a public GitHub repository about xunruicms RCE, but the bundle does not establish active exploitation. The issue is not marked as CISA KEV in the provided data. Treat public-facing instances as urgent because unauthenticated RCE has severe impact.
Researcher notes
Core severity and vulnerability class are clear, but public metadata is thin. The source bundle names xunruicms up to v4.5.1 and /index.php, yet lacks normalized affected products, CPEs, patch details, and verified exploitation status.
Mitigation direction
- Inventory all xunruicms deployments and identify versions.
- Check vendor or project guidance for a fixed release or mitigation.
- Remove, isolate, or restrict internet exposure for affected instances.
- Review access controls around /index.php while remediation is pending.
- Monitor web logs for suspicious crafted GET requests to /index.php.
Validation and detection
- Confirm whether xunruicms is deployed in production, staging, or legacy hosts.
- Verify whether any deployed version is 4.5.1 or earlier.
- Check whether /index.php is reachable from untrusted networks.
- Review recent web logs for unusual GET requests targeting /index.php.
- Document evidence gaps because CPE and fixed-version data are absent.
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-94: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. 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-2021-38243 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
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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.
CVSS vector scores
1 official scoreWe 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:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/P0wfuu/xunruicms-RCECVE reference
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 Control of Generation of Code ('Code Injection')
Improper Control of Generation of Code ('Code Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.