CVE Intelligence
High Injection

CVE-2026-115935 — Control panel only API response emulation replaces "securityKey" and reaches server RCE

The app/process-api-response-headers action accepts fake Craft API response headers from any authenticated control panel user. A non-admin user with only accessCp can place newline characters in X-Craft-Plugin-Licenses. Craft passes this value to its .env writer without removing the newlines. This lets the user insert a new attacker-known CRAFT_SECURITY_KEY into .env. After Craft loads that key, the user can forge a signed login redirect containing a Twig system() callback. This is different from the previous report. That report reads the existing key through a Twig sandbox bypass. This report replaces the key through fake API headers and CRLF injection. Fixing either source does not fix the other.

Published Oct 23, 2026 · Updated Oct 26, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Hackrate

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
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.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.37%
ahead of 31% of scored CVEs · Oct 29, 2026
Affects
Craftcms
Cms
CVSS base
8.8
High · 3 source(s)

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.

  1. Identify exposed assets running the affected vendor/product/version combinations (Craftcms Cms).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (injection), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Craftcms Cms ≥ 5.0.0 and < 5.11.2≥ 4.0.0 and < 4.18.9 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.7 CVSS 4.0 High — — 7004884b-51e2-48e8-b4a2-5ca29e80453e via NIST National Vulnerability Database
8.7 CVSS 4.0 High — — Hackrate via CVE Program (cve.org) e CISA ADP
8.8 CVSS 3.1 High 2.8 5.9 7004884b-51e2-48e8-b4a2-5ca29e80453e via NIST National Vulnerability Database
8.8 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.8 CVSS 3.1 High — — Hackrate 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: 7004884b-51e2-48e8-b4a2-5ca29e80453e)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-94 · Code Injection

Other CVEs with this weakness →

EPSS over time FIRST

Oct 24, 2026 → Oct 29, 2026 · 6 reading(s) · max 0.68%

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).
  • Look for parameters with command/query metacharacters and unexpected child processes of the service.
web/proxy/WAF logsnetwork IDS/IPSapplication logsendpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Source status changed · Received → Awaiting Analysis
    Oct 26, 2026 · NIST National Vulnerability Database
  • Affected products added · craftcms/cms
    Oct 23, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 23, 2026
  • CVSS changed · 8.8
    Oct 23, 2026 · NIST National Vulnerability Database
  • Source status changed · → Received
    Oct 23, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 23, 2026 · NIST National Vulnerability Database
  • CVE published
    Oct 23, 2026 · Hackrate

Source activity

Repeated readings are counted rather than listed.

  • 1× References added · Oct 26, 2026 – Oct 26, 2026
  • 1× Official description updated · Oct 23, 2026 – Oct 23, 2026

References

6 on the record

Elsewhere on this site

Craftcms
every CVE for this vendor
Injection
same class
CWE-94
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-115938 Low privilege condition filter escapes Twig sandbox, recovers "securityKey" and reaches RCE 6d
  • CVE-2026-112777 Craft CMS before 4.18.8 and 5.11.0 Twig create() Blocklist Bypass Leading to RCE 10d
  • CVE-2026-112773 Craft CMS 5.0.0 before 5.11.0 RCE via Twig Sandbox Behavior Injection 10d
  • CVE-2026-112770 Craft CMS before 4.18.8 and 5.11.0 Authenticated RCE via Twig group Filter Array-Callable 10d
  • CVE-2026-112772 Craft CMS 5.0.0 before 5.11.0 RCE via Asset::getMimeType Transform Injection 10d
  • CVE-2026-112771 Craft CMS before 4.18.8 and 5.11.0 Twig Sandbox Allowlist Bypass via Array Filters 10d

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 CISA SSVC assessment.
  • 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-2026-115935 is "Control panel only API response emulation replaces "securityKey" and reaches server RCE", rated High. It affects Cms (Craftcms); 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 0.37% 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.

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