A new zero-day named StyleSmuggler gives unauthenticated attackers remote code execution against every current version of Magento Open Source and Adobe Commerce, and it has been under active exploitation since September 4. Sansec published its research on September 5. Adobe's most recent Commerce security bulletin, meanwhile, still dates back to August 11, and as of this writing there's no advisory, CVE, or patch from the vendor.
Aikido Intel picked this up and rated it critical before Adobe had assigned a CVE number, and Aikido Libraries already has a working fix for multiple affected versions. This post covers how the exploit works, who it affects, and how to fix this, whether or not you're already an Aikido customer.
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The fix: what Aikido shipped
Aikido Libraries fixes vulnerable packages by swapping in a secured, drop-in replacement, so the store never needs a Magento or Adobe Commerce version upgrade and there's nothing new to regression-test. It’s the same upgrade trap we’ve written about elsewhere, except here there isn’t a new version to upgrade to. On a platform where a version bump routinely breaks extensions and customizations, teams can apply this over a weekend instead of opening a multi-week project with QA and vendor sign-off.
Aikido has released patches across the following branches:
- 2.3.1-p12007002+aikido
- 2.4.7-p1012007002+aikido
- 2.4.8-p512007002+aikido
Teams running the vulnerable package across multiple sites can push the fix out in bulk across every site at once.
The patch sanitizes template styles before Magento's engine processes them, closing the exact path StyleSmuggler uses to reach the platform's directive and dependency-injection processing. It's applied at two points depending on the version, matching the two ways the vulnerable code handles style data. Legitimate CSS passes through untouched.
Aikido Intel is the threat intelligence feed behind the detection. It tracks active exploits and zero-days as they surface, before a CVE ever gets assigned, and it has rated this one critical across every affected package: AIKIDO-2026-248927 for Magento Open Source, AIKIDO-2026-123768 for Adobe Commerce, and AIKIDO-2026-724507 for the Magento Cloud metapackage. Each entry documents the injection point and the trigger condition, so you can confirm exposure without waiting on Adobe.
If you're not an Aikido customer, the closest thing to an official mitigation right now is disabling GraphQL temporarily, since that's the entry point the exploit depends on. That's a real trade-off for any headless or PWA storefront, which goes offline the moment GraphQL is blocked, and even then it only hardens against the current attack pattern. The underlying flaw stays open until Adobe ships a real fix.
How StyleSmuggler works
The exploit runs in two stages, both abusing functionality Magento already has.
First, an unauthenticated attacker injects PHP through style properties on a GraphQL request. The payload doesn't execute immediately. It gets written into a file Magento generates itself, such as a failure report produced during a checkout error. Second, the payload executes later, when Magento renders a Payment Transaction Failed Reminder email. The email doesn't need to be delivered. The code runs server-side during template rendering, so the attack completes even if the message never reaches an inbox.
Confirmed intrusions have installed a persistent Rust-based backdoor disguised as a kernel thread. It survives a reboot and sits there waiting for instructions, sometimes for hours before doing anything at all. From there, the exposure is everything unauthenticated RCE on an e-commerce platform implies: customer PII, payment transaction details, admin credentials, database contents, and a route to Magecart-style skimmer injections against shoppers.
Who this affects
Every current version of Magento Open Source and Adobe Commerce is vulnerable, including 2.4.9. Sansec reproduced the full attack chain on clean installs of 2.4.7, 2.4.8, and 2.4.9. One confirmed victim was running 2.4.6-p15 with the July and August 2026 security patches fully applied. Patch status didn't save it.
Where Adobe stands
As of this writing, Adobe has not published an advisory, assigned a CVE identifier, or released a patch or workaround, and its most recent Commerce security bulletin still dates to August 11. Its next scheduled security release is September 8. Whether that covers StyleSmuggler is still unknown.
What to do right now
- Check your exposure against the Aikido Intel entry for your package: AIKIDO-2026-248927 (Magento Open Source), AIKIDO-2026-123768 (Adobe Commerce), or AIKIDO-2026-724507 (Magento Cloud metapackage).
- Apply the Aikido Libraries fix for your version, or disable GraphQL as an interim measure if you can't patch immediately.
- Don't wait on Adobe's September 8 release. It isn't confirmed to cover this.
- Rotate Magento credentials if you find any evidence of compromise, since the backdoor has been observed sitting dormant before activating.
We'll update this post as Adobe publishes further guidance.
FAQ
Is StyleSmuggler being actively exploited? Yes. Sansec confirmed attack traffic starting September 4, 2026, a day before public disclosure.
Do I need to be logged in or have a session for my site to be at risk? No. StyleSmuggler is unauthenticated, meaning attackers need no credentials, session, or user interaction to exploit it.
Does upgrading to the latest Magento version fix this? No. Magento 2.4.9, the latest release, is confirmed vulnerable along with 2.4.7 and 2.4.8.
Is there a patch from Adobe? Not yet. Adobe hasn't assigned a CVE or shipped a patch as of this writing.