How severe is GHSA-45vw-wh46-2vx8?

No CVSS score has been assigned to GHSA-45vw-wh46-2vx8 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-45vw-wh46-2vx8?

GHSA-45vw-wh46-2vx8 affects the following packages: twig/twig (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-45vw-wh46-2vx8?

Update twig/twig to 3.26.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-45vw-wh46-2vx8 is resolved across your whole dependency graph.

How do I detect GHSA-45vw-wh46-2vx8 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for twig/twig, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-45vw-wh46-2vx8 if there is no patch (or I can't update yet)?

Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Is GHSA-45vw-wh46-2vx8 actively exploited in the wild?

No public exploit code has been indexed for GHSA-45vw-wh46-2vx8 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-45vw-wh46-2vx8?

GHSA-45vw-wh46-2vx8 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 49th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-45vw-wh46-2vx8?

GHSA-45vw-wh46-2vx8 is classified as Code Injection (CWE-94). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-45vw-wh46-2vx8 published, and has it been updated?

GHSA-45vw-wh46-2vx8 was published on May 21, 2026 and was last updated on September 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

Not in CISA KEV

GHSA-45vw-wh46-2vx8 — twig/twig

GHSA-45vw-wh46-2vx8 is a Code Injection vulnerability in twig/twig. A fix is available for twig/twig — see the affected versions and patch details below.

Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation

Also known asCVE-2026-46640

Published

May 21, 2026

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-45vw-wh46-2vx8.

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs49th percentile — riskier than 49% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐘twig/twig

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

The obj.(expr) dynamic-attribute syntax (added in 3.15.0 as the replacement for the deprecated attribute() function) lets the attribute be an arbitrary expression. When the receiver is _self (or any {% import %} alias) and the parenthesised expression is a string literal, DotExpressionParser short-circuits to the macro-call path and concatenates the attacker-controlled string into a MacroReferenceExpression name with no identifier validation. MacroReferenceExpression::compile() then emits that name raw into the generated PHP source.

An attacker who can supply template source can inject arbitrary PHP into the compiled template and execute it at template-load time, before checkSecurity() is ever called. This is a complete bypass of SandboxExtension, including a globally-enabled sandbox with an empty SecurityPolicy allowlist.

Resolution

The parser now validates that the dynamic attribute resolves to a valid macro identifier before routing through MacroReferenceExpression, and the macro-reference compiler emits the name through a properly escaped path.

Credits

Twig would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`twig/twig`	≥ 3.15.0&&< 3.26.0	3.26.0`composer require twig/twig:^3.26.0`

Affected Products

1 product · 1 configurations

Application

twigsymfony

≥ 3.15.0 && < 3.26.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for twig/twig, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update twig/twig to 3.26.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-45vw-wh46-2vx8 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Frequently Asked Questions

### Description The `obj.(expr)` dynamic-attribute syntax (added in 3.15.0 as the replacement for the deprecated `attribute()` function) lets the attribute be an arbitrary expression. When the receiver is `_self` (or any `{% import %}` alias) and the parenthesised expression is a string literal, `DotExpressionParser` short-circuits to the macro-call path and concatenates the attacker-controlled string into a `MacroReferenceExpression` name with no identifier validation. `MacroReferenceExpression::compile()` then emits that name raw into the generated PHP source. An attacker who can supply te

O3 Security · Impact-Aware SCA

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GHSA-45vw-wh46-2vx8 — twig/twig

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

Real-World Exposure

Description

Description

Resolution

Credits

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is GHSA-45vw-wh46-2vx8 in your dependencies?