CVE-2021-28821 | TIBCO Enterprise Message Service Windows Platform Installation vulnerability

The Windows Installation component of TIBCO Software Inc.'s TIBCO Enterprise Message Service, TIBCO Enterprise Message Service - Community Edition, and TIBCO Enterprise Message Service - Developer Edition contains a vulnerability that theoretically allows a low privileged attacker with local access on some versions of the Windows operating system to insert malicious software. The affected component can be abused to execute the malicious software inserted by the attacker with the elevated privileges of the component. This vulnerability results from a lack of access restrictions on certain files and/or folders in the installation. Affected releases are TIBCO Software Inc.'s TIBCO Enterprise Message Service: versions 8.5.1 and below, TIBCO Enterprise Message Service - Community Edition: versions 8.5.1 and below, and TIBCO Enterprise Message Service - Developer Edition: versions 8.5.1 and below.

Published: 2021-03-23 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-28821 is rated Low Risk (39.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.22%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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

Exploit prediction scoring system (EPSS) score for CVE-2021-28821

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 0.04% 0.22% +0.17%
2 2026-01-12 0.13% 0.04% -0.08%
3 2025-11-21 — 0.13% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-28821

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
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.
 2.0 6.0 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
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.
 1.8 5.9 [email protected]
4.6 2.0 MEDIUM
AV:L/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:L)
Requires local access to the target system.
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.
 3.9 6.4 [email protected]

Weakness enumeration for CVE-2021-28821

Affected software / configurations for CVE-2021-28821

Vendor Product Version Raw CPE
tibco enterprise_message_service <= 8.5.1 cpe:2.3:a:tibco:enterprise_message_service:*:*:-:*:*:*:*:*
tibco enterprise_message_service <= 8.5.1 cpe:2.3:a:tibco:enterprise_message_service:*:*:community:*:*:*:*:*
tibco enterprise_message_service <= 8.5.1 cpe:2.3:a:tibco:enterprise_message_service:*:*:developer:*:*:*:*:*

References for CVE-2021-28821

cvelogic Threat Intelligence