Review reviewCritical

CVE-2021-47923

Opencart

OpenCart 3.0.3.8 contains a session fixation vulnerability that allows attackers to hijack user sessions by injecting arbitrary values into the OCSESSID cookie. Attackers can set malicious OCSESSID cookie values that the server accepts and maintains, enabling session takeover and unauthorized access to user accounts.

CVSS
9.3
EPSS
0.42%
34.8% percentile
CISA KEV
Not listed
Published
2026.05.10
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.42%
Technical severityCVSS 9.3

Vulnerability overview

OpenCart 3.0.3.8 contains a session fixation vulnerability that allows attackers to hijack user sessions by injecting arbitrary values into the OCSESSID cookie. Attackers can set malicious OCSESSID cookie values that the server accepts and maintains, enabling session takeover and unauthorized access to user accounts.

Affected product and versions

Product
Opencart
Affected versions
>= 3.0.3.8
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Opencart and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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
CWE
CWE-290
CVE-2021-47923 — Opencart | SECUFOCUS NOW