StackPrism

npm package

undici 6.28.0 vulnerabilities, and the version that fixes all of them

undici 6.28.0 has 3 known vulnerabilities (1 rated high or critical); 6.28.1 fixes all of them.

npm (opens in a new tab) describes it as “An HTTP/1.1 client, written from scratch for Node.js”

Known vulnerabilities
3
1 rated high or critical
Released
Jul 24, 2026
Latest is 8.12.2
Downloads last week
7.9M
4% of undici downloads
Licence
MIT
OpenSSF Scorecard
8.1/10
nodejs/undici (opens in a new tab)
Dependencies
None
Resolved by deps.dev

What to upgrade to

6.28.1 is the closest release with no known vulnerabilities.

  • 6.28.1Upgrade to this

    Fixes all 3 known vulnerabilities. Released Sep 4, 2026.

    No known vulnerabilities

  • 6.29.1

    Newest 6.x release. Released Oct 15, 2026.

    No known vulnerabilities

  • 8.12.2

    Latest release. Released Oct 15, 2026.

    No known vulnerabilities

6.28.1 came out on Sep 4, 2026. A coding agent trained before then doesn’t know it exists, so it may suggest an older release. AI knowledge cutoff dates

Hand the fix to your coding agent

One task with the upgrade, the file to change and why. Paste it into Claude Code, Cursor or Codex.

Findings

Every advisory for undici 6.28.0

Known exploited first (CISA KEV), then by how likely they are to be exploited (FIRST EPSS), then by severity. Each id links to its OSV.dev record.

  1. WarningCVE-2026-85024 on OSV.dev (opens in a new tab)GHSA-3wwx-pv8p-q78vEPSS: top 67%

    undici vulnerable to Denial of Service via unhandled error in WebSocket permessage-deflate decompression

    Fixed in 6.28.1. Published Sep 28, 2026.

  2. CriticalCVE-2026-19534 on OSV.dev (opens in a new tab)GHSA-rfgv-xxqx-mfg5EPSS: top 69%

    undici vulnerable to Denial of Service via unrequested WebSocket subprotocol

    Fixed in 6.28.1. Published Sep 29, 2026.

  3. LowCVE-2026-18540 on OSV.dev (opens in a new tab)GHSA-r53p-7pc4-xj5rEPSS: top 87%

    undici vulnerable to downstream response splitting via retry interceptor

    Fixed in 6.28.1. Published Sep 29, 2026.

Who is still on a vulnerable undici

51% of last week’s 217.5M undici downloads went to versions with known vulnerabilities.

From npm’s per-version download counts for the last 7 days, each version checked against OSV.dev. The versions checked cover over 99% of downloads.

Is undici the only one?

Paste a public GitHub repo or drop your package.json and see every vulnerable, end-of-life or deprecated dependency, with one fix task. Free, no sign-up.

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How this page is checked

StackPrism asks OSV.dev which advisories affect exactly undici 6.28.0, merges duplicates filed under several ids, and ranks them with CISA’s Known Exploited Vulnerabilities list and FIRST EPSS. Release dates and deprecation come from deps.dev and npm. No AI writes this page: every sentence comes from that data, refreshed every few hours.

Last checked against npm, OSV.dev, deps.dev, CISA KEV and FIRST EPSS.