CVE-2026-104871
Prior to versions 20.3.36, 21.2.23, and 22.1.7, the CommonEngine retrieveSSGPage prerendered-page retrieval logic in @angular/ssr/node, and in @angular/ssr for versions 17 through 18, accepts a relative request URL containing a backslash…
Does this matter?
Lower severity and a low EPSS score (0.42%). Track it; it rarely justifies an emergency change on its own.
Description
The Angular SSR is a server-rise rendering tool for Angular applications. Prior to versions 20.3.36, 21.2.23, and 22.1.7, the CommonEngine retrieveSSGPage prerendered-page retrieval logic in @angular/ssr/node, and in @angular/ssr for versions 17 through 18, accepts a relative request URL containing a backslash parent-traversal segment on Windows. The non-special resolve:// URL base preserves the backslash, path.join interprets it as a Windows separator, and the pagePath.startsWith(normalize(publicPath)) check incorrectly accepts a sibling output directory whose name shares the configured public-directory prefix. An unauthenticated requester can therefore retrieve a sibling prerendered HTML page when that page contains the Angular SSG marker. The issue is limited to Windows deployments that pass relative request URLs to CommonEngine.render, have a prefix-sharing sibling output directory, and contain qualifying prerendered Angular HTML; it does not provide arbitrary file read. This issue is fixed in versions 20.3.36, 21.2.23, and 22.1.7.
- CVSS 4.0
- 6.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.42% probability · 36th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- security-advisories@github.com
EPSS moved from 0.4% on 3 October 2026 to 0.4% on 26 October 2026.
References
- https://github.com/angular/angular-cli/commit/645e41a47d21b7651837a4250de99af0509626e2
- https://github.com/angular/angular-cli/commit/70748ca8e76fe4b42798719410336119d943e755
- https://github.com/angular/angular-cli/commit/bb72145f9ab45aee29f523236b3a25cd0813a841
- https://github.com/angular/angular-cli/commit/c3e5982e49705f0f6a913cb94622b4c555d2d914
- https://github.com/angular/angular-cli/releases/tag/v20.3.36
- https://github.com/angular/angular-cli/releases/tag/v21.2.23
- https://github.com/angular/angular-cli/releases/tag/v22.1.7
- https://github.com/angular/angular-cli/security/advisories/GHSA-7g7c-h8rr-7p6q
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.