CVE-2025-12346 — MaxSite CMS HTTP Header uploads-require-maxsite.php unrestricted upload
A vulnerability was detected in MaxSite CMS up to 109. This vulnerability affects unknown code of the file application/maxsite/admin/plugins/auto_post/uploads-require-maxsite.php of the component HTTP Header Handler. Performing manipulation of the argument X-Requested-FileName/X-Requested-FileUpDir results in unrestricted upload. Remote exploitation of the attack is possible. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.4% (30-day exploitation probability)+5
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Max-3000 Maxsite Cms, MaxSite CMS).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (file handling), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Max-3000 | Maxsite Cms | ≤ 109 | Vulnerable | NIST National Vulnerability Database |
| MaxSite | CMS | version 109 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 5.3 | CVSS 4.0 | Medium | — | — | VulDB via CVE Program (cve.org) e CISA ADP |
| 2.1 | CVSS 4.0 | Low | — | — | cna@vuldb.com via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 6.3 | CVSS 3.1 | Medium | 2.8 | 3.4 | cna@vuldb.com via NIST National Vulnerability Database |
| 6.3 | CVSS 3.1 | Medium | — | — | VulDB via CVE Program (cve.org) e CISA ADP |
| 6.3 | CVSS 3.0 | Medium | — | — | VulDB via CVE Program (cve.org) e CISA ADP |
| 6.5 | CVSS 2.0 | Medium | 8.0 | 6.4 | cna@vuldb.com via NIST National Vulnerability Database |
| 6.5 | CVSS 2.0 | Medium | — | — | VulDB via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.40%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Monitor file creation in web directories and paths with traversal sequences (../).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · maxsite/cms
- SSVC assessment updated
- Record published
- CVSS changed · 8.8
- Source status changed · → Analyzed
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
4 on the record
Elsewhere on this site
Related CVEs (same products)
- Low CVE-2026-7016 MaxSite CMS ushki Plugin cross site scripting Apr 26, 2026
- Low CVE-2026-7015 MaxSite CMS Guestbook Plugin cross site scripting Apr 26, 2026
- Low CVE-2026-7013 MaxSite CMS mail_send Plugin cross site scripting Apr 26, 2026
- Low CVE-2026-7014 MaxSite CMS down_count Plugin cross site scripting Apr 26, 2026
- Low CVE-2026-7012 MaxSite CMS Redirect Plugin cross site scripting Apr 25, 2026
- Low CVE-2026-7011 MaxSite CMS Antispam Plugin plugin_antispam cross site scripting Apr 25, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-12346 is "MaxSite CMS HTTP Header uploads-require-maxsite.php unrestricted upload", rated High. It affects Maxsite Cms (Max-3000); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.8 describes technical severity. EPSS 0.40% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.