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GHSA-h6m7-j4h3-9rf5

CriticalCVSS 9.6 / 10
Published Aug 19, 2020·Last modified Mar 13, 2026
Affected Components(0)

No affected components available

Description

Impact

Request parameters injected inside an expression evaluated by symfony/expression-language package haven't been sanitized properly. This allows the attacker to access any public service by manipulating that request parameter, allowing for Remote Code Execution.

The vulnerable versions include: <=1.3.13 || >=1.4.0 <=1.4.6 || >=1.5.0 <=1.5.1 || >=1.6.0 <=1.6.3.

Example

sylius_grid:
    grids:
        foo:
            fields:
                bar:
                    options:
                        baz: "expr:service('sylius.repository.product').find($id)"

In this case, $id can be prepared in a way that calls other services.

If you visit /route?id="~service('doctrine').getManager().getConnection().executeQuery("DELETE * FROM TABLE")~", it will result in a following expression expr:service('repository').find(""~service('doctrine').getManager().getConnection().executeQuery("DELETE * FROM TABLE")~""), which will execute a query on the currently connected database.

To find a vulnerability in your application, look for any routing definition that uses request parameters inside expression language.

Patches

This issue has been patched for versions 1.3.14, 1.4.7, 1.5.2 and 1.6.4. Versions prior to 1.3 were not patched.

Workarounds

The fix requires adding addslashes in OptionsParser::parseOptionExpression to sanitize user input before evaluating it using the expression language.

- return is_string($variable) ? sprintf('"%s"', $variable) : $variable;
+ return is_string($variable) ? sprintf('"%s"', addslashes($variable)) : $variable;

Acknowledgements

This security issue has been reported by Craig Blanchette (@isometriks), thanks a lot!

For more information

If you have any questions or comments about this advisory:

Risk Scores
Base Score
9.6

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The vulnerability can affect other systems as well, not just the initial system. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data.

Threat Intelligence
8.8

Exploitation activity has been observed. Apply available patches or mitigations urgently.

EPSS
2.15%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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