CVE-2026-85024
published 2026-09-04CVE-2026-85024: undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error…
PriorityP432medium5.9CVSS 3.1
AVNACHPRNUINSUCNINAH
EPSS
0.41%
34.4th percentile
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a fatal unhandled error and terminates the entire process. Exploitation is remote and unauthenticated, requires no application mistake, and is asymmetric, since roughly 130 KB on the wire expands past the limit and crashes the process, and reconnecting can repeat the crash. This affects undici versions from 6.25.0 up to 6.28.1, from 7.28.0 up to 7.29.1, and from 8.1.0 up to 8.10.2. Users should upgrade to undici 6.28.1, 7.29.1, or 8.10.2.
Affected
54 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| ansible-automation-platform | automation-portal | — | — |
| ansible-automation-platform | bootc-automation-portal-rhel9 | — | — |
| devspaces | code-rhel9 | — | — |
| devspaces | dashboard-rhel9 | — | — |
| devspaces | openvsx-rhel9 | — | — |
| devspaces | pluginregistry-rhel9 | — | — |
| exploit-intelligence | vulnerability-analysis-rhel9 | — | — |
| external-secrets-management | console-plugin-rhel9 | — | — |
| grafana | grafana | — | — |
| nodejs | undici | >= 6.25.0 < 6.28.1 | 6.28.1 |
| nodejs | undici | >= 7.28.0 < 7.29.1 | 7.29.1 |
| nodejs | undici | >= 8.1.0 < 8.10.2 | 8.10.2 |
| nodejs_22 | nodejs | — | — |
| nodejs_24 | nodejs | — | — |
| nodejs_26 | nodejs | — | — |
| odf4 | mcg-core-rhel9 | — | — |
| odf4 | ocs-client-console-rhel9 | — | — |
| odf4 | odf-console-rhel9 | — | — |
| odf4 | odf-multicluster-console-rhel9 | — | — |
| openshift-pipelines | pipelines-console-plugin-pf5-rhel9 | — | — |
| openshift-pipelines | pipelines-console-plugin-rhel9 | — | — |
| openshift4 | ose-monitoring-plugin-rhel9 | — | — |
| rhdh | red-hat-developer-hub-backstage-plugin-lightspeed-backend | — | — |
| rhdh | red-hat-developer-hub-backstage-plugin-orchestrator-backend | — | — |
| rhdh | red-hat-developer-hub-backstage-plugin-orchestrator-backend-module-loki | — | — |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
vendor_redhat5.9MEDIUM
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Red Hat
undici: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression
vendor_redhat·2026-09-04·CVSS 5.9
CVE-2026-85024 [MEDIUM] CWE-431 undici: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression
undici: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression
A flaw was found in undici. A remote, unauthenticated attacker can trigger a Denial of Service (DoS) by sending a specially crafted compressed WebSocket payload. When this payload exceeds the 128 MiB decompressed-payload limit and contains a malformed DEFLATE byte, it causes an unhandled error in the internal zlib inflate stream. This unhandled error leads to the termination of the entire Node.js process, making the service unavailable.
Package: exploit-intelligence/vulnerability-analysis-rhel9 (Exploit Intelligence) - Out of support scope
Package: openshift-pipelines/pipelines-console-plugin-pf5-rhel9 (OpenShift Pipelines) - Fix deferred
Package: openshift-pipelines/pipelines-console-pl
GHSA
undici vulnerable to Denial of Service via unhandled error in WebSocket permessage-deflate decompression
ghsa·2026-09-28
CVE-2026-85024 [MEDIUM] CWE-248 undici vulnerable to Denial of Service via unhandled error in WebSocket permessage-deflate decompression
undici vulnerable to Denial of Service via unhandled error in WebSocket permessage-deflate decompression
## Impact
undici's WebSocket client (including Node.js's bundled `globalThis.WebSocket`) crashes the entire Node.js process when a remote WebSocket peer sends a permessage-deflate compressed message that crosses the decompressed-payload size limit and then contains a malformed DEFLATE block. In `lib/web/websocket/permessage-deflate.js`, the size-limit cleanup calls `removeAllListeners()` on the internal zlib `InflateRaw`, removing its `error` listener, but leaves the stream running. The inflater then emits a `Z_DATA_ERROR` with no listener attached, which Node.js treats as a fatal unhandled `error` event and terminates the process. Application `error`/`close` handlers on the public We
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-85024 nodejs22: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
bugzilla·2026-09-09·CVSS 5.9
CVE-2026-85024 [MEDIUM] CVE-2026-85024 nodejs22: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
CVE-2026-85024 nodejs22: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a
Bugzilla
CVE-2026-85024 nodejs24: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
bugzilla·2026-09-09·CVSS 5.9
CVE-2026-85024 [MEDIUM] CVE-2026-85024 nodejs24: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
CVE-2026-85024 nodejs24: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a
Bugzilla
CVE-2026-85024 fbthrift: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
bugzilla·2026-09-09·CVSS 5.9
CVE-2026-85024 [MEDIUM] CVE-2026-85024 fbthrift: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
CVE-2026-85024 fbthrift: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a
Bugzilla
CVE-2026-85024 nodejs20: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
bugzilla·2026-09-09·CVSS 5.9
CVE-2026-85024 [MEDIUM] CVE-2026-85024 nodejs20: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
CVE-2026-85024 nodejs20: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a
Bugzilla
CVE-2026-85024 undici: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression
bugzilla·2026-09-04·CVSS 5.9
CVE-2026-85024 [MEDIUM] CVE-2026-85024 undici: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression
CVE-2026-85024 undici: undici: Denial of Service via unhandled error in WebSocket permessage-deflate decompression
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a fatal unhandled error and terminates the entire process. Exploitation is remote and unauthenticated, requires no application mistake, and is asymmetric, since roughly 130 KB on the wire expands past the limit and crashes the process, and r
2026-09-04
Published