# [CRIT] [GHSA / CRITICAL] CVE-2026-46633: Twig: PHP code injection via `{% use %}` template name

**Source:** GitHub Security Advisories
**Published:** 2026-05-21
**Article:** https://github.com/advisories/GHSA-7p85-w9px-jpjp

## Threat Profile

Twig: PHP code injection via `{% use %}` template name

### Description

`Compiler::string()` escapes `"`, `$`, `\`, NUL and TAB when generating PHP double-quoted string literals, but does not escape single quotes. In `ModuleNode::compileConstructor()`, the template name from a `{% use %}` tag is compiled via `subcompile()` -> `string()` and placed inside a surrounding PHP single-quoted string literal. A template name containing a single quote terminates that surrounding string early, allowing a…

## Indicators of Compromise (high-fidelity only)

- **CVE:** `CVE-2026-46633`

## MITRE ATT&CK Techniques

- **T1190** — Exploit Public-Facing Application

## Kill chain phases observed

_(none detected from narrative keywords)_

## Recommended hunts

### Vulnerable Twig package (CVE-2026-46633) installed (twig/twig < 3.26.0)

`UC_225_1` · phase: **exploit** · confidence: **High** · AI-generated for this article

**Splunk SPL (CIM):**
```spl
| tstats summariesonly=t count, min(_time) as firstTime, max(_time) as lastTime from datamodel=Vulnerabilities where (Vulnerabilities.cve="CVE-2026-46633" OR (Vulnerabilities.signature="twig/twig" OR Vulnerabilities.signature="composer:twig/twig" OR Vulnerabilities.signature="twig")) by Vulnerabilities.dest, Vulnerabilities.dest_category, Vulnerabilities.signature, Vulnerabilities.cve, Vulnerabilities.severity, Vulnerabilities.cvss
| `drop_dm_object_name(Vulnerabilities)`
| where isnotnull(dest)
| convert ctime(firstTime) ctime(lastTime)
| sort - cvss
```

**Defender KQL:**
```kql
// CVE-2026-46633 — Twig {% use %} PHP code injection (vuln < 3.26.0)
DeviceTvmSoftwareVulnerabilities
| where CveId == "CVE-2026-46633"
    or (SoftwareName has "twig" and SoftwareVendor has "twig")
| join kind=leftouter (
    DeviceTvmSoftwareInventory
    | where SoftwareName has "twig" and SoftwareVendor has "twig"
    | project DeviceId, InstalledVersion = SoftwareVersion
) on DeviceId
| project Timestamp, DeviceName, OSPlatform, OSVersion,
          SoftwareVendor, SoftwareName, SoftwareVersion, InstalledVersion,
          CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId
| order by VulnerabilitySeverityLevel desc, DeviceName asc
```

### IOC-driven hunts (use shared templates)

These are standard IOC-substitution hunts — the canonical SPL and KQL live once in [`_TEMPLATES.md`](../_TEMPLATES.md), so we don't repeat the same boilerplate on every CVE / hash / network-IOC briefing.

- **Asset exposure — vulnerability matches article CVE(s)** ([template](../_TEMPLATES.md#asset-exposure)) — phase: **recon**, confidence: **High**
  - CVE(s): `CVE-2026-46633`


## Why this matters

Severity classified as **CRIT** based on: CVE present, 2 use case(s) fired, 1 technique(s) inferred. Read the full article for actor attribution, tooling details, and any defanged IOCs in the body that aren't visible in the RSS summary.