CVE-2026-12151
highpriority · track · 0EPSS 0.008 · 56 %ileDEEUNLUSEPSS · scored 2026-10-27
Impact: The undici WebSocket client enforces maxPayloadSize on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size validation, collectively causing unbounded memory growth in the client process. The result is memory exhaustion and a denial of service. Affected applications are those using the undici WebSocket client (new WebSocket(...)) or the WebSocketStream API that can be induced to connect to an attacker-controlled or compromised WebSocket endpoint. All releases starting at undici 6.17.0 are affected. Patches: Upgrade to undici >= 6.26.0, >= 7.28.0, or >= 8.5.0. Workarounds: No workaround is available. The fix must be applied through an upgrade.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (47)
Products and version ranges known to be affected.
advisories (5)
Vendor and ecosystem advisories describing this.
- NCSC-2026-0325Kwetsbaarheden verholpen in Atlassian productenNL2026-08-24csaf · ncsc_nlNL
Atlassian heeft kwetsbaarheden verholpen in diverse producten zoals Bamboo, Bitbucket, Confluence, Jira, Crowd en Fisheye. De kwetsbaarheden bevinden zich in diverse Third-Party producten waar eerder updates voor zijn verschenen. Atlassian heeft deze updates verwerkt in de eigen producten.
- WID-SEC-W-2026-2618IBM App Connect Enterprise: Mehrere SchwachstellenDeutsch2026-08-02csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM App Connect Enterprise ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, und um Daten zu manipulieren.
- WID-SEC-W-2026-2919IBM App Connect Enterprise: Mehrere SchwachstellenDeutsch2026-08-18csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM App Connect Enterprise ausnutzen, um beliebigen Programmcode auszuführen, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, und um Sicherheitsvorkehrungen zu umgehen.
- WID-SEC-W-2026-2923Atlassian Produkte (Bamboo, Bitbucket, Confluence, Crucible, Fisheye, und Jira): Mehrere SchwachstellenDeutsch2026-08-18csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Atlassian Bitbucket, Atlassian Confluence, Atlassian Crucible, Atlassian Fisheye und Atlassian Jira ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, um einen SQL-Injection Angriff durchzuführen, und um Sicherheitsvorkehrungen zu umgehen.
- GHSA-vxpw-j846-p89qundici WebSocket client vulnerable to denial of service via fragment count bypass2026-06-19ghsa · osvUS
## Impact The undici WebSocket client enforces `maxPayloadSize` on the cumulative byte count of fragments in a message but does not enforce a limit on the number of fragments. A malicious WebSocket server can stream many small or empty continuation frames that each pass per-frame and cumulative-size validation, collectively causing unbounded memory growth in the client process. The result is memory exhaustion and a denial of service. Affected applications are those using the undici WebSocket client (`new WebSocket(...)`) or the `WebSocketStream` API that can be induced to connect to an attacker-controlled or compromised WebSocket endpoint. All releases starting at undici 6.17.0 are affected. ## Patches Upgrade to undici v6.27.0, v7.28.0 or v8.5.0. ## Workarounds No workaround is available. The fix must be applied through an upgrade.
also known as (3)
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sources
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references (35)
External citations — patches, advisories, analysis.
- https://cna.openjsf.org/security-advisories.htmlcnnvd
- https://github.com/nodejs/undici/security/advisories/GHSA-vxpw-j846-p89qcnnvd
- https://cna.openjsf.org/security-advisories.htmlenisa_euvd
- https://github.com/nodejs/undici/security/advisories/GHSA-vxpw-j846-p89qenisa_euvd
- https://access.redhat.com/errata/RHSA-2026:34342nvd
- https://access.redhat.com/errata/RHSA-2026:35841nvd
- https://access.redhat.com/errata/RHSA-2026:35842nvd
- https://access.redhat.com/errata/RHSA-2026:35891nvd
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