How severe is CVE-2026-1011?

CVE-2026-1011 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-2026-1011 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-1011?

CVE-2026-1011 affects Altium Altium Live. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-1011?

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

Does CVE-2026-1011 have an EU (EUVD) identifier?

Yes. CVE-2026-1011 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2999.

When was CVE-2026-1011 published?

CVE-2026-1011 was published on 2026-01-16 and last updated on 2026-06-17.

CVE-2026-1011

CVE-2026-1011 is a medium-severity vulnerability in Altium Altium Live 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2999
Weakness: CWE-79
Affected product: Altium Altium Live
Published: 2026-01-16
Last modified: 2026-06-17

Description

A stored cross-site scripting (XSS) vulnerability exists in the Altium Support Center AddComment endpoint due to missing server-side input sanitization. Although the client interface applies HTML escaping, the backend accepts and stores arbitrary HTML and JavaScript supplied via modified POST requests. The injected content is rendered verbatim when support cases are viewed by other users, including support staff with elevated privileges, allowing execution of arbitrary JavaScript in the victim’s browser context.

Frequently asked questions

What is CVE-2026-1011?: A stored cross-site scripting (XSS) vulnerability exists in the Altium Support Center AddComment endpoint due to missing server-side input sanitization. Although the client interface applies HTML escaping, the backend accepts and stores arbitrary HTML and JavaScript supplied via modified POST requests. The injected content is rendered verbatim when support cases are viewed by other users, including support staff with elevated privileges, allowing execution of arbitrary JavaScript in the victim’s browser context.
How severe is CVE-2026-1011?: CVE-2026-1011 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-2026-1011 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-1011?: CVE-2026-1011 affects Altium Altium Live. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-1011?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-1011 have an EU (EUVD) identifier?: Yes. CVE-2026-1011 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2999.
When was CVE-2026-1011 published?: CVE-2026-1011 was published on 2026-01-16 and last updated on 2026-06-17.

References

https://www.altium.com/platform/security-compliance/security-advisories

Affected products (1)

cpe:2.3:a:altium:altium_live:*:*:*:*:*:*:*:*

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