CVE-2026-42155

CRITICAL EPSS 18.3%
Published May 15, 20261mo ago · Modified Jun 17, 20262w ago
9.3 CVSS 4.0
Critical
Find Similar
Published May 15, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Prior to 20.18.0, the XML-RPC / SOAP API session ID is generated using an outdated, time-based construction rather than a Cryptographically Secure Pseudo-Random Number Generator (CSPRNG). All inputs to the MD5 hash are time-derived and non-secure. Because the resulting digest relies entirely on the timestamp and the PHP internal LCG state, the effective entropy is severely constrained. This violates the OWASP ASVS v4 requirement of ≥ 64 bits of entropy (V3.2.2) and NIST SP 800-63B standards. By narrowing the LCG window (via server state leaks or general predictability) and leveraging the lack of API rate-limiting, an attacker can generate a localized pool of candidate MD5 hashes and execute a high-speed online brute-force attack to hijack active API sessions. This vulnerability is fixed in 20.18.0.

CVSS Details

Base Score
9.3
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
18.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 3

CWE-330
CWE-331
CWE-338

References 1

  • github.com https://github.com/OpenMage/magento-lts/security/advisories/GHSA-2cwr-gcf9-pvxr

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.