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CVE-2023-2017NVD status: Modified

Shopware 6: Improper Control of Generation of Code

CVE-2023-2017 is a high-severity improper control of generation of code vulnerability in Shopware 6 from Shopware, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Shopware 6 versions: 6.4.20.0 and earlier; 6.5.0.0-rc1 through 6.5.0.0-rc4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 2.07% chance of exploitation within 30 days, higher than 82% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Shopware 6 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on docs.shopware.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
ShopwareShopware 66.4.20.0 and earlier; 6.5.0.0-rc1 through 6.5.0.0-rc4Not stated
ShopwareShopware6.1.0 through 6.4.20.0; 6.5.0.0Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCNA (starlabs.sg)
CVSS 3.18.8HighNVD

Official description

Server-side Template Injection (SSTI) in Shopware 6 (<= v6.4.20.0, v6.5.0.0-rc1 <= v6.5.0.0-rc4), affecting both shopware/core and shopware/platform GitHub repositories, allows remote attackers with access to a Twig environment without the Sandbox extension to bypass the validation checks in `Shopware\Core\Framework\Adapter\Twig\SecurityExtension` and call any arbitrary PHP function and thus execute arbitrary code/commands via usage of fully-qualified names, supplied as array of strings, when referencing callables. Users are advised to upgrade to v6.4.20.1 to resolve this issue. This is a bypass of CVE-2023-22731.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

How developers prevent this class of flaw

  • Refactor your program so that you do not have to dynamically generate code.
  • Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
  • Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

More Improper Control of Generation of Code vulnerabilities (CWE-94)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Recent Improper Control of Generation of Code vulnerabilities

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