CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NCVE-2026-120423
Medium (5.9) in undici undici. EPSS 0.1% estimated probability of exploitation activity in the next 30 days.
On this page
undici is an HTTP client for Node.js. In versions 7.15.0 through 7.30.1 and 8.0.0 through 8.12.3, fetch verifies Subresource Integrity metadata by splitting the integrity string on a single space, but the SRI grammar separates metadata by ASCII whitespace, which also includes the horizontal tab. An integrity value whose digest is preceded by a tab or other ASCII whitespace is parsed as a single unrecognized token and skipped, and when no recognized algorithm remains undici treats the integrity list as empty and accepts the response, so a server returning a body different from the pinned digest passes the check. An application that pins a response with a valid but whitespace-surrounded SRI value receives attacker-controlled bytes with no integrity error, and the attacker needs only to control the response body, not the integrity metadata. The issue is fixed in undici 7.30.2 and 8.12.4, and users should upgrade to one of those versions or later. As a workaround, supply SRI integrity metadata without surrounding whitespace, using a single space to separate multiple digests.
Severity
- EPSS
- 0.1% estimated probability of exploitation activity in the next 30 days; 3rd percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-354 Improper Validation of Integrity Check Value
- Published
- Modified
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| undici | from 7.15.0 before 7.30.2 |
| undici | from 8.0.0 before 8.12.4 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | node-undici | no fix listed | DEBIAN-CVE-2026-120423 |
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 | node-undici | no fix listed | UBUNTU-CVE-2026-120423 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.
Attack patterns (CAPEC)
- CAPEC-75 Manipulating Writeable Configuration Files Likelihood: High · Severity: Very High
- CAPEC-145 Checksum Spoofing Severity: Medium
- CAPEC-463 Padding Oracle Crypto Attack Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.