Is undici 6.19 vulnerable?

npm · 9 releases from 6.19.0 to 6.19.8 · latest undici is 8.12.3 · checked 1 Nov 2026

Yes: 21 known advisories

Yes. undici 6.19.8, the last 6.19 release, is affected by 21 known security advisories (7 high, 10 medium, 4 low), including CVE-2026-109383, CVE-2026-87018, CVE-2026-19534. 1 more affects earlier 6.19.x releases. Upgrade to 6.29.1 or later to fix all of them.

Upgrade with:npm install undici@6.29.1

Is your project affected?

Private repo? Upload its lockfile instead, or connect GitHub to check every repo.

Advisories affecting undici 6.19.8

  • HighCVE-2026-109383GHSA-2m5v-pch6-74hx27 Oct 2026

    undici vulnerable to TLS certificate validation bypass via dropped tls options in Agent

    Affected
    >=4.0.0 <6.29.1 · >=7.0.0 <7.30.1 · >=8.0.0 <8.12.2
    Fixed in
    6.29.1, 7.30.1, 8.12.2
  • HighCVE-2026-87018GHSA-qrxm-fqhp-jwvm27 Oct 2026

    undici vulnerable to Denial of Service via TLS 1.2 certificate-changing renegotiation

    Affected
    >=4.2.1 <6.29.1 · >=7.0.0 <7.30.1 · >=8.0.0 <8.12.2
    Fixed in
    6.29.1, 7.30.1, 8.12.2
  • MediumCVE-2026-109932GHSA-9fm3-97px-rjf627 Oct 2026

    undici WebSocket client vulnerable to Denial of Service via unbounded automatic PONG buffering

    Affected
    >=5.15.0 <6.29.1 · >=7.0.0 <7.30.1 · >=8.0.0 <8.12.2
    Fixed in
    6.29.1, 7.30.1, 8.12.2
  • MediumCVE-2026-109924GHSA-4qv8-2p9j-268523 Oct 2026

    undici vulnerable to Denial of Service via unbounded memory in the EventSource parser

    Affected
    >=6.5.0 <6.29.1 · >=7.0.0 <7.30.1 · >=8.0.0 <8.12.2
    Fixed in
    6.29.1, 7.30.1, 8.12.2
  • LowCVE-2026-18540GHSA-r53p-7pc4-xj5r29 Sept 2026

    undici vulnerable to downstream response splitting via retry interceptor

    Affected
    <6.28.1 · >=7.0.0 <7.29.1 · >=8.0.0 <8.10.2
    Fixed in
    6.28.1, 7.29.1, 8.10.2
  • HighCVE-2026-19534GHSA-rfgv-xxqx-mfg529 Sept 2026

    undici vulnerable to Denial of Service via unrequested WebSocket subprotocol

    Affected
    >=6.7.0 <6.28.1 · >=7.0.0 <7.29.1 · >=8.0.0 <8.10.2
    Fixed in
    6.28.1, 7.29.1, 8.10.2
  • MediumCVE-2026-15157GHSA-m8rv-5g2x-5cg53 Aug 2026

    undici vulnerable to CRLF Injection via blob-like body 'type' property

    Affected
    <6.28.0 · >=7.0.0 <7.29.0 · >=8.0.0 <8.9.0
    Fixed in
    6.28.0, 7.29.0, 8.9.0
  • MediumCVE-2026-16729GHSA-v3r7-h72x-cjcm3 Aug 2026

    undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fields

    Affected
    <6.28.0 · >=7.0.0 <7.29.0 · >=8.0.0 <8.9.0
    Fixed in
    6.28.0, 7.29.0, 8.9.0
  • MediumCVE-2026-16728GHSA-8xcm-r25x-g5243 Aug 2026

    undici vulnerable to downstream response desynchronization via retry interceptor

    Affected
    <6.28.0 · >=7.0.0 <7.29.0 · >=8.0.0 <8.9.0
    Fixed in
    6.28.0, 7.29.0, 8.9.0
  • LowCVE-2026-11525GHSA-g8m3-5g58-fq7m19 Jun 2026

    undici vulnerable to Set-Cookie SameSite attribute downgrade via permissive substring matching

    Affected
    <6.27.0 · >=7.0.0 <7.28.0 · >=8.0.0 <8.5.0
    Fixed in
    6.27.0, 7.28.0, 8.5.0
  • HighCVE-2026-12151GHSA-vxpw-j846-p89q19 Jun 2026

    undici WebSocket client vulnerable to denial of service via fragment count bypass

    Affected
    <6.27.0 · >=7.0.0 <7.28.0 · >=8.0.0 <8.5.0
    Fixed in
    6.27.0, 7.28.0, 8.5.0
  • MediumCVE-2026-9679GHSA-p88m-4jfj-68fv19 Jun 2026

    undici vulnerable to HTTP header injection via Set-Cookie percent-decoding

    Affected
    <6.27.0 · >=7.0.0 <7.28.0 · >=8.0.0 <8.5.0
    Fixed in
    6.27.0, 7.28.0, 8.5.0
  • LowCVE-2026-6733GHSA-35p6-xmwp-9g5219 Jun 2026

    undici vulnerable to HTTP response queue poisoning via keep-alive socket reuse

    Affected
    <6.27.0 · >=7.0.0 <7.28.0 · >=8.0.0 <8.5.0
    Fixed in
    6.27.0, 7.28.0, 8.5.0
  • HighCVE-2026-1526GHSA-vrm6-8vpv-qv8q13 Mar 2026

    Undici has Unbounded Memory Consumption in WebSocket permessage-deflate Decompression

    Affected
    <6.24.0 · >=7.0.0 <7.24.0
    Fixed in
    6.24.0, 7.24.0
  • HighCVE-2026-2229GHSA-v9p9-hfj2-hcw813 Mar 2026

    Undici has Unhandled Exception in WebSocket Client Due to Invalid server_max_window_bits Validation

    Affected
    <6.24.0 · >=7.0.0 <7.24.0
    Fixed in
    6.24.0, 7.24.0
  • MediumCVE-2026-1527GHSA-4992-7rv2-5pvq13 Mar 2026

    Undici has CRLF Injection in undici via `upgrade` option

    Affected
    <6.24.0 · >=7.0.0 <7.24.0
    Fixed in
    6.24.0, 7.24.0
  • HighCVE-2026-1528GHSA-f269-vfmq-vjvj13 Mar 2026

    Undici: Malicious WebSocket 64-bit length overflows parser and crashes the client

    Affected
    >=6.0.0 <6.24.0 · >=7.0.0 <7.24.0
    Fixed in
    6.24.0, 7.24.0
  • MediumCVE-2026-1525GHSA-2mjp-6q6p-2qxm13 Mar 2026

    Undici has an HTTP Request/Response Smuggling issue

    Affected
    <6.24.0 · >=7.0.0 <7.24.0
    Fixed in
    6.24.0, 7.24.0
  • MediumCVE-2026-22036GHSA-g9mf-h72j-4rw914 Jan 2026

    Undici has an unbounded decompression chain in HTTP responses on Node.js Fetch API via Content-Encoding leads to resource exhaustion

    Affected
    >=7.0.0 <7.18.2 · <6.23.0
    Fixed in
    6.23.0, 7.18.2
  • LowCVE-2025-47279GHSA-cxrh-j4jr-qwg315 May 2025

    undici Denial of Service attack via bad certificate data

    Affected
    <5.29.0 · >=6.0.0 <6.21.2 · >=7.0.0 <7.5.0
    Fixed in
    5.29.0, 6.21.2, 7.5.0
  • MediumCVE-2025-22150GHSA-c76h-2ccp-497521 Jan 2025

    Use of Insufficiently Random Values in undici

    Affected
    >=4.5.0 <5.28.5 · >=6.0.0 <6.21.1 · >=7.0.0 <7.2.3
    Fixed in
    5.28.5, 6.21.1, 7.2.3

Fixed within 6.19.x, affecting earlier releases

  • LowCVE-2024-38372GHSA-3g92-w8c5-73pq9 Jul 2024

    Undici vulnerable to data leak when using response.arrayBuffer()

    Affected
    >=6.14.0 <6.19.2
    Fixed in
    6.19.2

Which of your client projects are still on undici 6.19?

NPMscan reads the lockfiles in every GitHub repo you pick, finds the exact undici version each one installs, and checks it against these advisories. Each finding comes with the command that fixes it.

Other undici versions

Advisory data from OSV.dev (opens OSV.dev in a new tab), which includes the GitHub Advisory Database. Release list from the npm registry. Refreshed daily.