CVE-2021-47923
CVE-2021-47923 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-290.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v4: 9.3
- EPSS exploit prediction: 0% (34th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2021-34785
- Weakness: CWE-290
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2021-47923?
- 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.
- How severe is CVE-2021-47923?
- CVE-2021-47923 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-47923 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2021-47923?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- Does CVE-2021-47923 have an EU (EUVD) identifier?
- Yes. CVE-2021-47923 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34785.
- When was CVE-2021-47923 published?
- CVE-2021-47923 was published on 2026-05-10 and last updated on 2026-06-17.
References
- https://www.exploit-db.com/exploits/50555
- https://www.opencart.com/
- https://www.vulncheck.com/advisories/opencart-session-fixation-via-ocsessid-cookie
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