How severe is CVE-2026-22551?

CVE-2026-22551 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-22551 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-22551?

CVE-2026-22551 affects Eclipse Theia. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-22551?

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

Does CVE-2026-22551 have an EU (EUVD) identifier?

Yes. CVE-2026-22551 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37900.

When was CVE-2026-22551 published?

CVE-2026-22551 was published on 2026-06-18 and last updated on 2026-06-22.

CVE-2026-22551

CVE-2026-22551 is a medium-severity vulnerability in Eclipse Theia with a CVSS 3.x base score of 6.5. 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-201.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 6.7
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-37900
Weakness: CWE-201
Affected product: Eclipse Theia
Published: 2026-06-18
Last modified: 2026-06-22

Description

In Eclipse Theia versions prior to 1.71.0, the AI chat rendered Markdown image tags from AI responses, triggering HTTP requests to arbitrary external URLs without restriction. Combined with prompt injection in a malicious workspace, an attacker could induce the AI agent to construct image URLs encoding sensitive information from the workspace or conversation context, exfiltrating it to attacker-controlled servers. The workspace trust enforcement introduced in v1.71.0 mitigates the documented attack chain by disabling AI features in untrusted workspaces.

Frequently asked questions

What is CVE-2026-22551?: In Eclipse Theia versions prior to 1.71.0, the AI chat rendered Markdown image tags from AI responses, triggering HTTP requests to arbitrary external URLs without restriction. Combined with prompt injection in a malicious workspace, an attacker could induce the AI agent to construct image URLs encoding sensitive information from the workspace or conversation context, exfiltrating it to attacker-controlled servers. The workspace trust enforcement introduced in v1.71.0 mitigates the documented attack chain by disabling AI features in untrusted workspaces.
How severe is CVE-2026-22551?: CVE-2026-22551 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-22551 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-22551?: CVE-2026-22551 affects Eclipse Theia. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-22551?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-22551 have an EU (EUVD) identifier?: Yes. CVE-2026-22551 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37900.
When was CVE-2026-22551 published?: CVE-2026-22551 was published on 2026-06-18 and last updated on 2026-06-22.

References

https://gitlab.eclipse.org/security/cve-assignment/-/work_items/115

Affected products (1)

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

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