CVE-2026-109841
published 2026-10-15CVE-2026-109841: undici is an HTTP client library for Node.js. In versions 7.15.0 through 7.30.0 and 8.0.0 through 8.12.1, its fetch() implementation verifies Subresource…
PriorityP344high7.5CVSS 3.1
AVNACLPRNUINSUCNIHAN
EPSS
0.25%
15.7th percentile
undici is an HTTP client library for Node.js. In versions 7.15.0 through 7.30.0 and 8.0.0 through 8.12.1, its fetch() implementation verifies Subresource Integrity metadata by matching the algorithm token against a lowercase-only set, even though the SRI specification defines the token by its ASCII-lowercase form, so a valid but non-lowercase token such as an uppercase or mixed-case SHA256 is treated as unknown and skipped. When no recognized algorithm remains, undici treats the integrity list as empty and accepts the response, so a server returning a body that does not match the pinned digest passes the check. An attacker who controls only the response body can therefore deliver attacker-controlled bytes to an application that pinned a valid uppercase or mixed-case SRI token, with no integrity error, affecting response integrity only. The issue is fixed in undici 7.30.1 and 8.12.2, which normalize the algorithm token to ASCII lowercase before validation, and users should upgrade to one of those versions or later. As a workaround, use lowercase algorithm tokens such as sha256, sha384, or sha512 in integrity metadata.
Affected
51 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| ansible-automation-platform | automation-portal | — | — |
| ansible-automation-platform | bootc-automation-portal-rhel9 | — | — |
| cryostat | cryostat-openshift-console-plugin-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 | >= 7.15.0 < 7.30.1 | 7.30.1 |
| nodejs | undici | >= 8.0.0 < 8.12.2 | 8.12.2 |
| 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 | — | — |
| 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 | — | — |
| rhdh | red-hat-developer-hub-backstage-plugin-scaffolder-backend-module-orchestrator | — | — |
| rhdh | rhdh-hub-rhel9 | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
vendor_redhat5.9MEDIUM
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Red Hat
undici: undici: Subresource Integrity bypass via non-lowercase algorithm tokens
vendor_redhat·2026-10-15·CVSS 5.9
CVE-2026-109841 [MEDIUM] CWE-354 undici: undici: Subresource Integrity bypass via non-lowercase algorithm tokens
undici: undici: Subresource Integrity bypass via non-lowercase algorithm tokens
A flaw was found in undici. The HTTP client improperly handles case sensitivity when verifying Subresource Integrity (SRI) algorithm tokens. When an application specifies an uppercase or mixed-case algorithm name, undici treats the token as unrecognized and skips verification instead of enforcing it. A remote attacker who controls the HTTP response body can exploit this flaw to deliver modified content without triggering an integrity error, bypassing intended security protections.
Package: cryostat/cryostat-openshift-console-plugin-rhel9 (Cryostat 4) - Fix deferred
Package: exploit-intelligence/vulnerability-analysis-rhel9 (Exploit Intelligence) - Out of support scope
Package: amq-broker-bin.zip (Red Hat AM
GHSA
undici vulnerable to Subresource Integrity bypass via non-lowercase algorithm tokens
ghsa·2026-10-23
CVE-2026-109841 [MEDIUM] CWE-178 undici vulnerable to Subresource Integrity bypass via non-lowercase algorithm tokens
undici vulnerable to Subresource Integrity bypass via non-lowercase algorithm tokens
### Impact
undici's `fetch()` verifies Subresource Integrity (SRI) metadata by looking up the algorithm token in a lowercase-only set, but the SRI specification defines a valid token by its ASCII-lowercase form. A correct but non-lowercase token such as `SHA256-...` or `Sha256-...` is therefore treated as unknown and skipped. When no recognized algorithm remains, undici treats the integrity list as empty and accepts the response, so a server that returns a body different from the pinned digest passes the check.
An application that pins a response with a valid uppercase or mixed-case SRI token receives attacker-controlled bytes with no integrity error. The attacker needs only to control the response body
No detection rules found.
No public exploits indexed.
2026-10-15
Published