How severe is CVE-2021-28162?

CVE-2021-28162 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-28162 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28162?

CVE-2021-28162 affects Eclipse Theia. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-28162?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-28162 published?

CVE-2021-28162 was published on 2021-03-12 and last updated on 2026-06-17.

CVE-2021-28162

CVE-2021-28162 is a medium-severity vulnerability in Eclipse Theia with a CVSS 3.x base score of 6.1. 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-829.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-829
Affected product: Eclipse Theia
Published: 2021-03-12
Last modified: 2026-06-17

Description

In Eclipse Theia versions up to and including 0.16.0, in the notification messages there is no HTML escaping, so Javascript code can run.

Frequently asked questions

What is CVE-2021-28162?: In Eclipse Theia versions up to and including 0.16.0, in the notification messages there is no HTML escaping, so Javascript code can run.
How severe is CVE-2021-28162?: CVE-2021-28162 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-28162 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28162?: CVE-2021-28162 affects Eclipse Theia. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-28162?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-28162 published?: CVE-2021-28162 was published on 2021-03-12 and last updated on 2026-06-17.

References

https://github.com/eclipse-theia/theia/issues/7283

Affected products (1)

cpe:2.3:a:eclipse:theia:*:*:*:*:*:*:*:*

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