CVE-2021-47923Public exploitNetwork attack vectorHinoki check available

Unauthenticated session takeover via reflected OCSESSID

Published May 10, 2026 · Updated May 10, 2026

Session fixation in OpenCart 3.0.3.8 allows remote attackers to hijack user sessions by supplying a chosen OCSESSID cookie. OpenCart's session-cookie processing accepts the attacker-selected value and returns the same identifier in Set-Cookie instead of generating a fresh value. The published record requires no prior privileges or user interaction; successful fixation enables unauthorized account access.

CVSS severity9.3
Critical
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Session fixation in OpenCart 3.0.3.8 allows remote attackers to hijack user sessions by supplying a chosen OCSESSID cookie. OpenCart's session-cookie processing accepts the attacker-selected value and returns the same identifier in Set-Cookie instead of generating a fresh value. The published record requires no prior privileges or user interaction; successful fixation enables unauthorized account access.

The record

CVE
CVE-2021-47923
Published
May 10, 2026
Updated
May 10, 2026
Vendor
OpenCart
Product
OpenCart
Classifications
CWE-290, T1550.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 10, 2026CVE publishedPublication date reported by the CVE source.
  2. May 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.0.3.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenCart · OpenCartversion=3.0.3.8

Published CVSS scores

9.8VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-290Authentication Bypass by Spoofing
T1550.004Web Session Cookie

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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