EUVD-2026-29794Published

sse-channel: SSE Injection via unsanitized event fields

Collected exploitation and prediction evidence

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.

cve-program · CVE-2026-44217

Published

sse-channel is an SSE-implementation which can be used to any node.js http request/response stream. Prior to 4.0.1, implementations that allow user-provided values to be passed to event, retry or id fields are susceptible to event spoofing, where an attacker could inject arbitrary messages into the stream. This vulnerability is fixed in 4.0.1.

Source published: 12 May 2026 19:51:06 UTC
Source modified: 14 May 2026 19:52:02 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

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: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 6.6 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

euvd · EUVD-2026-29794

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: May 12, 2026, 7:51:06 PM

dateUpdated: May 14, 2026, 7:52:02 PM

Source published: May 12, 2026, 7:51:06 PM (timezone not stated)
Source modified: May 14, 2026, 7:52:02 PM (timezone not stated)
Observed here: 7 Nov 2026 10:29:30 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 4.0 · 6.6 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

nvd · CVE-2026-44217

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Deferred

Weakness classifications: CWE-93

Original publisher date fields

published: 2026-05-12T20:16:42.513

lastModified: 2026-10-26T18:10:00.173

Source published: 12 May 2026 20:16:42 UTC
Source modified: 26 Oct 2026 18:10:00 UTC
Observed here: 27 Oct 2026 11:12:09 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 4.0 · [email protected] · Secondary · 6.6 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

osv · GHSA-84hm-wfh8-c5pg

Published

### Impact Implementations that allows user-provided values to be passed to `event`, `retry` or `id` fields would be susceptible to event spoofing, where an attacker could inject arbitrary messages into the stream. - **Event Spoofing:** Attacker can inject arbitrary SSE events into the stream - **Client-side Manipulation:** Injected events can trigger unintended behavior in frontend JavaScript EventSource listeners - **Data Integrity:** Consumers of the SSE stream cannot distinguish injected events from legitimate ones ### Patches Patch available in v4.0.1. ### Workarounds Do not allow user data to control `event`, `retry` or `id` fields, and if you must - sanitize the input before passing it to `sse-channel`, stripping any newlines. ### Resources https://github.com/rexxars/sse-channel/issues/42

Source published: 5 May 2026 22:17:02 UTC
Source modified: 13 May 2026 16:46:23 UTC
Observed here: 24 Oct 2026 13:17:17 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

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: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U

Publisher rating · MODERATE