Security readout for executives and security teams
Plain-English summary
Vvveb versions before 1.0.8.1 can allow an unauthenticated remote attacker to run PHP code through an exposed installation endpoint. Successful compromise would give the attacker the web server’s privileges, potentially enabling data theft, website modification, service disruption, or further internal access.
Executive priority
Treat internet-facing affected systems as an immediate remediation priority. The issue can permit complete application compromise without authentication or user action. Upgrade promptly, temporarily restrict the installation endpoint, and investigate exposed systems for tampering. Internal or unreachable deployments remain important but can follow verified externally accessible instances.
Technical view
The installation endpoint writes the subdir POST parameter into env.php without adequate escaping or validation. Crafted input can escape the intended PHP string context and inject executable PHP. The CVSS 3.1 score is 9.8 because exploitation is remote, low-complexity, requires no privileges or user interaction, and can compromise confidentiality, integrity, and availability.
Likely exposure
Highest risk applies to internet-accessible Vvveb installations earlier than 1.0.8.1 where the installation endpoint remains reachable. Exposure cannot be determined from version alone; endpoint accessibility, deployed code, and configuration-file integrity must be checked. The structured affected-version entry is ambiguous, although the title and description consistently state versions before 1.0.8.1.
Exploitation context
The supplied record marks this CVE as absent from KEV and provides no cited evidence of active exploitation. That does not establish that exploitation has never occurred. The vulnerability’s unauthenticated, network-accessible, low-complexity characteristics make exposed systems attractive targets, but current real-world exploitation prevalence is unknown from the supplied sources.
Researcher notes
The patch reference is commit 5162c1639130bd080ab63c7d856788cd59d6b3b7, associated with release 1.0.8.1. The supplied affected array lists version 0 and that commit hash while defaulting other versions to unaffected, which conflicts with the narrative range. Use the stated pre-1.0.8.1 range cautiously and confirm against vendor artifacts.
Mitigation direction
- Upgrade Vvveb to version 1.0.8.1 or later using vendor guidance.
- Restrict external access to the installation endpoint until the upgrade is verified.
- Review env.php for unauthorized changes and restore it from a trusted source if necessary.
- Rotate credentials or secrets accessible to the web server if compromise indicators are found.
Validation and detection
- Confirm the deployed Vvveb version is 1.0.8.1 or later.
- Verify the installation endpoint is removed, disabled, or inaccessible to untrusted users.
- Compare env.php and application files against trusted release artifacts.
- Review web and application logs for suspicious installation-endpoint requests.
- Check for unexpected PHP files, processes, accounts, or configuration changes.
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-2026-39918 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.
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:N/UI:N/S:U/C:H/I:H/A:H3.95.9VulnCheckCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
9.2CriticalVector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
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
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
- https://github.com/givanz/Vvveb/releases/tag/1.0.8.1CVE reference, VulnCheck · release-notes
- https://github.com/givanz/Vvveb/commit/5162c1639130bd080ab63c7d856788cd59d6b3b7CVE reference, VulnCheck · patch
- https://www.vulncheck.com/advisories/vvveb-code-injection-via-installation-endpointCVE 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 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.