How severe is CVE-2021-28821?

CVE-2021-28821 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-28821 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28821?

CVE-2021-28821 primarily affects Tibco Enterprise Message Service. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-28821?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-28821 published?

CVE-2021-28821 was published on 2021-03-23 and last updated on 2026-06-17.

CVE-2021-28821

CVE-2021-28821 is a high-severity vulnerability in Tibco Enterprise Message Service with a CVSS 3.x base score of 8.8. 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-863.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Tibco Enterprise Message Service
Published: 2021-03-23
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-28821?: 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.
How severe is CVE-2021-28821?: CVE-2021-28821 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-28821 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28821?: CVE-2021-28821 primarily affects Tibco Enterprise Message Service. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-28821?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-28821 published?: CVE-2021-28821 was published on 2021-03-23 and last updated on 2026-06-17.

References

http://www.tibco.com/services/support/advisories

Affected products (3)

cpe:2.3:a:tibco:enterprise_message_service:*:*:-:*:*:*:*:*
cpe:2.3:a:tibco:enterprise_message_service:*:*:community:*:*:*:*:*
cpe:2.3:a:tibco:enterprise_message_service:*:*:developer:*:*:*:*:*

More vulnerabilities in Tibco Enterprise Message Service

CVE-2009-1291 — Critical (CVSS 10.0): Stack-based buffer overflow in TIBCO SmartSockets before 6.8.2, SmartSockets Product Family (aka RTworks) before 4.0.5,…
CVE-2008-1704 — Critical (CVSS 10.0): Multiple buffer overflows in TIBCO Software Enterprise Message Service (EMS) before 4.4.3, and iProcess Engine 10.6.0…
CVE-2007-5655 — Critical (CVSS 10.0): TIBCO SmartSockets RTserver 6.8.0 and earlier, RTworks before 4.0.4, and Enterprise Message Service (EMS) 4.0.0 through…
CVE-2007-5658 — Critical (CVSS 10.0): Heap-based buffer overflow in TIBCO SmartSockets RTserver 6.8.0 and earlier, RTworks before 4.0.4, and Enterprise…
CVE-2007-5656 — Critical (CVSS 10.0): TIBCO SmartSockets RTserver 6.8.0 and earlier, RTworks before 4.0.4, and Enterprise Message Service (EMS) 4.0.0 through…
CVE-2007-5657 — Critical (CVSS 10.0): TIBCO SmartSockets RTserver 6.8.0 and earlier, RTworks before 4.0.4, and Enterprise Message Service (EMS) 4.0.0 through…

All CVEs affecting Tibco Enterprise Message Service →

Other CWE-863 (Incorrect Authorization) vulnerabilities

CVE-2026-48286 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) versions 7.4.3 build 9396 and earlier are affected by an Incorrect Authorization…
CVE-2026-48303 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) versions 7.4.3 build 9394 and earlier are affected by an Incorrect Authorization…
CVE-2026-44330 — Critical (CVSS 10.0): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the…
CVE-2026-46595 — Critical (CVSS 10.0): Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of…
CVE-2026-33105 — Critical (CVSS 10.0): Improper authorization in Microsoft Azure Kubernetes Service allows an unauthorized attacker to elevate privileges over…
CVE-2026-32213 — Critical (CVSS 10.0): Improper authorization in Azure AI Foundry allows an unauthorized attacker to elevate privileges over a network.

Browse all CWE-863 (Incorrect Authorization) vulnerabilities →