CVE-2021-33816

Exp

The website builder module in Dolibarr 13.0.2 allows remote PHP code execution because of an incomplete protection mechanism in which system, exec, and shell_exec are blocked but backticks are not blocked.

Published: 2021-11-10 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-33816 is rated High Exploit Risk (86.5/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 3.82%). 3 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.24% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-33816

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-33816

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 2.57% 3.82% +1.24%
2 2025-05-06 2.44% 2.57% +0.13%
3 2025-03-30 — 2.44% —

Full EPSS history (26 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-33816

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2021-33816

GitHub Security Advisory for CVE-2021-33816

GHSA-vxr9-p2xw-m8cf · Severity: critical · Ecosystem: composer — Dolibarr remote PHP code execution

OS Trackers for CVE-2021-33816

vendor priority summary link
ubuntu medium CVE-2021-33816 medium priority: Ubuntu including 1 source packages (dolibarr), 3 status rows across 3 suites (trusty, upstream, xenial): ignored 1, needed 1, needs-triage 1. https://ubuntu.com/security/CVE-2021-33816

Affected software / configurations for CVE-2021-33816

Vendor Product Version Raw CPE
dolibarr dolibarr_erp\/crm 13.0.2 cpe:2.3:a:dolibarr:dolibarr_erp\/crm:13.0.2:*:*:*:*:*:*:*

References for CVE-2021-33816

URL Tags
http://seclists.org/fulldisclosure/2021/Nov/39 Exploit Mailing List Third Party Advisory
https://trovent.github.io/security-advisories/TRSA-2106-01/TRSA-2106-01.txt Exploit Third Party Advisory
https://trovent.io/security-advisory-2106-01 Exploit Third Party Advisory
cvelogic Threat Intelligence