`vega-functions` vulnerable to Cross-site Scripting via `setdata` function

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

vega-functions provides function implementations for the Vega expression language. Prior to version 6.1.1, for sites that allow users to supply untrusted user input, malicious use of an internal function (not part of the public API) could be used to run unintentional javascript (XSS). This issue is fixed in vega-functions `6.1.1`. There is no workaround besides upgrading. Using `vega.expressionInterpreter` as described in CSP safe mode does not prevent this issue.

Source published

5 Jan 2026 21:33:14 UTC

Source modified

6 Jan 2026 15:40:18 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

vega-functions provides function implementations for the Vega expression language. Prior to version 6.1.1, for sites that allow users to supply untrusted user input, malicious use of an internal function (not part of the public API) could be used to run unintentional javascript (XSS). This issue is fixed in vega-functions `6.1.1`. There is no workaround besides upgrading. Using `vega.expressionInterpreter` as described in CSP safe mode does not prevent this issue.

Source published

Jan 5, 2026, 9:33:14 PM (timezone not stated)

Source modified

Jan 6, 2026, 3:40:18 PM (timezone not stated)

Observed here

9 Nov 2026 04:09:54 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

vega-functions provides function implementations for the Vega expression language. Prior to version 6.1.1, for sites that allow users to supply untrusted user input, malicious use of an internal function (not part of the public API) could be used to run unintentional javascript (XSS). This issue is fixed in vega-functions `6.1.1`. There is no workaround besides upgrading. Using `vega.expressionInterpreter` as described in CSP safe mode does not prevent this issue.

Source published

5 Jan 2026 22:15:51 UTC

Source modified

14 Oct 2026 19:10:00 UTC

Observed here

25 Oct 2026 03:17:36 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 7.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

CVSS 3.1 · [email protected] · Primary · 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

### Impact For sites that allow users to supply untrusted user input, malicious use of an internal function (not part of the [public API](https://vega.github.io/vega/docs/expressions/)) could be used to run unintentional javascript (XSS). ### Patches Fixed in vega-functions `6.1.1` ### Workarounds There is no workaround besides upgrading. Using `vega.expressionInterpreter` as described in [CSP safe mode](https://vega.github.io/vega/usage/interpreter/) does not prevent this issue. ### Exploit Proof of Concept Vega's expression `modify()` [function](https://github.com/vega/vega/blob/d8add5819346e5af597d82ef8253742acc0283ba/packages/vega-functions/src/functions/modify.js#L40), used by setdata, allows attacker to control both the method called and the values supplied, which results to XSS . This was a previous POC: ```json { "$schema": "https://vega.github.io/schema/vega/v6.json", "data": [ { "name": "table", "values": [ {"category": "A", "amount": 28} ] } ], "signals": [ { "name": "tooltip", "value": {}, "on": [ {"events": {"type":"timer","throttle":2000}, "update": "setdata('table',[['Domain: '+event.dataflow._el.ownerDocument.domain+' , cookies: '+ event.dataflow._el.ownerDocument.cookie ]])+warn('XSS is here', modify('table',2,3,null,event.dataflow._el.ownerDocument.defaultView.alert,{'tttt':'yyyy'}) )"}, {"events": "rect:pointerout", "update": "{}"} ] } ] } ```

Source published

5 Jan 2026 22:58:07 UTC

Source modified

10 Sep 2026 03:50:33 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Publisher rating · HIGH