# CVE-2026-49981: Twig: Sandbox filter, tag and function allow-list bypass when sandbox state changes between renders for a cached `Template`

> Attackers can bypass Twig sandbox restrictions by exploiting cached template states, allowing execution of disallowed filters or functions.

- **Severity:** Medium 6.0 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Jul 2026
- **Updated:** 21 Jul 2026
- **Also known as:** DEBIAN-CVE-2026-49981, GHSA-529h-vh3j-85hq, ROOT-APP-COMPOSER-CVE-2026-49981, UBUNTU-CVE-2026-49981

## What is CVE-2026-49981?

CVE-2026-49981 is a medium-severity vulnerability in twigphp Twig, published on 14 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Twig is a template language for PHP. Prior to 3.27.0, the per-template filter, tag, and function allow-list verdict is computed when a Template instance is constructed and can remain cached after sandbox state changes between renders, allowing a later sandboxed render to reuse a template that was originally checked with a different or empty policy. This issue is fixed in version 3.27.0.

Weakness: CWE-863 (Incorrect Authorization), CWE-693 (Protection Mechanism Failure)

## Which versions are affected by CVE-2026-49981?

2 open source packages ship an affected version, including twig/twig. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `twig/twig` | Packagist | All versions | 3.27.0 |
| `twig/twig` | Packagist | All versions | 3.27.0 |

Products: Symfony Twig.

## How do I fix CVE-2026-49981?

Upgrade twig/twig to 3.27.0 or later.

## Is CVE-2026-49981 being exploited?

There is no known exploitation of CVE-2026-49981 in the wild and no public exploit code.

## Other vulnerabilities in twigphp Twig

- [CVE-2018-13818](https://insights.sbomify.com/CVE-2018-13818/): Code injection in n/a (critical 9.8)
- [CVE-2026-46633](https://insights.sbomify.com/CVE-2026-46633/): Twig: PHP code injection via `{% use %}` template name (high 8.7)
- [CVE-2026-46640](https://insights.sbomify.com/CVE-2026-46640/): Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation (high 8.7)
- [CVE-2026-24425](https://insights.sbomify.com/CVE-2026-24425/): Twig 2.16.x & 3.9.0-3.25.x Sandbox Bypass via SourcePolicyInterface (high 8.7)
- [CVE-2024-45411](https://insights.sbomify.com/CVE-2024-45411/): Twig has a possible sandbox bypass (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49981 and fix it if it is affected.

What it is: CVE-2026-49981 is a medium-severity vulnerability in twigphp Twig, published on 14 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-49981 in the wild and no public exploit code.

Affected packages and fixed versions:
- twig/twig (Packagist): affected all versions; fixed in 3.27.0
- twig/twig (Packagist): affected all versions; fixed in 3.27.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-49981/ (Markdown: https://insights.sbomify.com/CVE-2026-49981/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49981
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49981
- OSV: https://osv.dev/vulnerability/CVE-2026-49981

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-49981/
Summaries are generated and may contain mistakes; the official description above is the record.
