E-commerce security company Sansec has warned that threat actors have begun to exploit a recently disclosed security vulnerability in Adobe Commerce and Magento Open Source platforms, with more than 250 attack attempts recorded against multiple stores over the past 24 hours.
The vulnerability in question is CVE-2025-54236 (CVSS score: 9.1), a critical improper input validation flaw that could be abused to take over customer accounts in Adobe Commerce through the Commerce REST API.
Also known as SessionReaper, it was addressed by Adobe last month. A security researcher who goes by the name Blaklis is credited with the discovery and responsible disclosure of CVE-2025-54236.
The Dutch company said that 62% of Magento stores remain vulnerable to the security flaw six weeks after public disclosure, urging website administrators to apply the patches as soon as possible before broader exploitation activity picks up.
The attacks have originated from the following IP addresses, with unknown threat actors leveraging the flaw to drop PHP webshells or probe phpinfo to extract PHP configuration information.
- 34.227.25[.]4
- 44.212.43[.]34
- 54.205.171[.]35
- 155.117.84[.]134
- 159.89.12[.]166
"PHP backdoors are uploaded via '/customer/address_file/upload' as a fake session," Sansec said.
The development comes as Searchlight Cyber published a detailed technical analysis of CVE-2025-54236, describing it as a nested deserialization flaw that enables remote code execution.
It's worth noting that CVE-2025-54236 is the second deserialization vulnerability impacting Adobe Commerce and Magento platforms in as many years. In July 2024, another critical flaw dubbed CosmicSting (CVE-2024-34102, CVSS score: 9.8) was subjected to widespread exploitation.
With proof-of-concept (PoC) exploits and additional specifics now entering public domains, it's imperative that users move quickly to apply the fixes.