CVE
Vvveb remote code execution in theme installer
Vvveb through 1.0.8.6 is affected, and the advisory's condition is nginx deployments using the bundled nginx-live.conf. No fixed version is listed.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- See vendor advisory
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. Runs on nginx using the bundled nginx-live.conf, which has no PHP deny rule for /themes/
- Published
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 22/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Vvveb through 1.0.8.6 contains a file upload vulnerability in the theme installer validFile() function that uses strpos() instead of strict path matching. Attackers with admin credentials can upload a ZIP containing a PHP file whose path includes /theme.php to achieve remote code execution on nginx deployments.
Who should check
Teams running Vvveb 1.0.8.6 or earlier on nginx with the bundled nginx-live.conf, and admins who can upload themes.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure8/25Specific setups only, reachable over the network
- Reach?/20Unknown. No tracked technology or package matched
- Severity9.4/10CVSS 9.4
- No patch5/5No fixed version listed; see vendor advisory
What would change the score
- Would score about 72 if added to CISA KEV
- Would score about 67 if CISA's SSVC rates exploitation active
- Would score about 29 if CISA's SSVC rates it automatable
What to do
Check whether your setup matches what the bug needs.
Runs on nginx using the bundled nginx-live.conf, which has no PHP deny rule for /themes/Workaround: The checked facts name no workaround. The condition the advisory names is the missing PHP deny rule for /themes/ in nginx-live.conf.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-126378 (Vvveb through 1.0.8.6 Webshell Upload via Theme Installer validFile() Bypass), using the cve.now data below.
Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.
What cve.now has for CVE-2026-126378 (entry last updated 2026-11-13):
Affected:
- givanz Vvveb: through 1.0.8.6
Fixed versions: none listed yet.
Conditions (all must be true for the bug to be hit):
- Runs on nginx using the bundled nginx-live.conf, which has no PHP deny rule for /themes/ (source: https://github.com/givanz/Vvveb/security/advisories/GHSA-xpgr-r6c8-3hpq)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, high-privilege login, no user action.
CISA KEV: CVE-2026-126378 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-126378 only. If you also check another CVE, look up its own KEV status; never assume it from this one.
How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.
Verify against the linked advisories before concluding, and cite the date you read each one:
- https://github.com/givanz/Vvveb/security/advisories/GHSA-xpgr-r6c8-3hpq
- https://www.vulncheck.com/advisories/vvveb-through-1.0.8.6-webshell-upload-via-theme-installer-validfile-bypass
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-126378
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-126378"}.Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- givanz Vvveb
through 1.0.8.6
Evidence 4
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Advisory
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-126378
Is CVE-2026-126378 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
An authenticated admin user can upload a webshell through the theme installer because the validFile() check can be bypassed. This can lead to remote code execution on the server as the web process user.Source: github.com
Which versions are affected by CVE-2026-126378?
Vvveb: through 1.0.8.6.Source: cve.now feed data
Am I affected, and how do I check?
Vvveb versions through 1.0.8.6 are in the advisory's range. The condition it names is nginx deployments using the bundled nginx-live.conf, which has no PHP deny rule for /themes/. Check the installed version and whether the server config matches that condition.Source: github.com
How do I fix CVE-2026-126378?
The checked facts name no fixed version and no vendor patch ids, so no upgrade target is given. Check the advisory for a newer release or patch before relying on this page.Source: github.com
What if there's no patch?
The checked facts name no workaround. The condition the advisory names is the missing PHP deny rule for /themes/ in nginx-live.conf.Source: github.com