How severe is CVE-2026-42277?

CVE-2026-42277 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-42277 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42277?

CVE-2026-42277 affects Onyx. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42277?

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

Does CVE-2026-42277 have an EU (EUVD) identifier?

Yes. CVE-2026-42277 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28525.

When was CVE-2026-42277 published?

CVE-2026-42277 was published on 2026-05-08 and last updated on 2026-06-17.

CVE-2026-42277

CVE-2026-42277 is a medium-severity vulnerability in Onyx 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-639.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28525
Weakness: CWE-639
Affected product: Onyx
Published: 2026-05-08
Last modified: 2026-06-17

Description

Onyx is an open-source AI platform. Prior to versions 3.0.9, 3.1.6, and 3.2.6, the GET /chat/file/{file_id} endpoint allows any authenticated user to download any other user's uploaded files by providing the file UUID. The endpoint verifies the caller is authenticated but never checks that the file belongs to them. An attacker who knows or obtains a file UUID can access confidential documents, chat attachments, and other files uploaded by any user in the system. This issue has been patched in versions 3.0.9, 3.1.6, and 3.2.6.

Frequently asked questions

What is CVE-2026-42277?: Onyx is an open-source AI platform. Prior to versions 3.0.9, 3.1.6, and 3.2.6, the GET /chat/file/{file_id} endpoint allows any authenticated user to download any other user's uploaded files by providing the file UUID. The endpoint verifies the caller is authenticated but never checks that the file belongs to them. An attacker who knows or obtains a file UUID can access confidential documents, chat attachments, and other files uploaded by any user in the system. This issue has been patched in versions 3.0.9, 3.1.6, and 3.2.6.
How severe is CVE-2026-42277?: CVE-2026-42277 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-42277 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42277?: CVE-2026-42277 affects Onyx. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42277?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-42277 have an EU (EUVD) identifier?: Yes. CVE-2026-42277 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28525.
When was CVE-2026-42277 published?: CVE-2026-42277 was published on 2026-05-08 and last updated on 2026-06-17.

References

https://github.com/onyx-dot-app/onyx/security/advisories/GHSA-vg3h-35f7-7w6r

Affected products (1)

cpe:2.3:a:onyx:onyx:*:*:*:*:*:*:*:*

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