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Vulnerability Details :

CVE-2026-27738

Summary
Assigner-GitHub_M
Assigner Org ID-a0819718-46f1-4df5-94e2-005712e83aaa
Published At-25 Feb, 2026 | 16:40
Updated At-27 Feb, 2026 | 20:46
Rejected At-
Credits

Angular SSR has an Open Redirect via X-Forwarded-Prefix

The Angular SSR is a server-rise rendering tool for Angular applications. An Open Redirect vulnerability exists in the internal URL processing logic in versions on the 19.x branch prior to 19.2.21, the 20.x branch prior to 20.3.17, and the 21.x branch prior to 21.1.5 and 21.2.0-rc.1. The logic normalizes URL segments by stripping leading slashes; however, it only removes a single leading slash. When an Angular SSR application is deployed behind a proxy that passes the `X-Forwarded-Prefix` header, an attacker can provide a value starting with three slashes. This vulnerability allows attackers to conduct large-scale phishing and SEO hijacking. In order to be vulnerable, the application must use Angular SSR, the application must have routes that perform internal redirects, the infrastructure (Reverse Proxy/CDN) must pass the `X-Forwarded-Prefix` header to the SSR process without sanitization, and the cache must not vary on the `X-Forwarded-Prefix` header. Versions 21.2.0-rc.1, 21.1.5, 20.3.17, and 19.2.21 contain a patch. Until the patch is applied, developers should sanitize the `X-Forwarded-Prefix` header in their`server.ts` before the Angular engine processes the request.

Vendors
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Not available
Products
-
Metrics (CVSS)
VersionBase scoreBase severityVector
Weaknesses
Attack Patterns
Solution/Workaround
References
HyperlinkResource Type
EPSS History
Score
Latest Score
-
N/A
No data available for selected date range
Percentile
Latest Percentile
-
N/A
No data available for selected date range
Stakeholder-Specific Vulnerability Categorization (SSVC)
▼Common Vulnerabilities and Exposures (CVE)
cve.org
Assigner:GitHub_M
Assigner Org ID:a0819718-46f1-4df5-94e2-005712e83aaa
Published At:25 Feb, 2026 | 16:40
Updated At:27 Feb, 2026 | 20:46
Rejected At:
▼CVE Numbering Authority (CNA)
Angular SSR has an Open Redirect via X-Forwarded-Prefix

The Angular SSR is a server-rise rendering tool for Angular applications. An Open Redirect vulnerability exists in the internal URL processing logic in versions on the 19.x branch prior to 19.2.21, the 20.x branch prior to 20.3.17, and the 21.x branch prior to 21.1.5 and 21.2.0-rc.1. The logic normalizes URL segments by stripping leading slashes; however, it only removes a single leading slash. When an Angular SSR application is deployed behind a proxy that passes the `X-Forwarded-Prefix` header, an attacker can provide a value starting with three slashes. This vulnerability allows attackers to conduct large-scale phishing and SEO hijacking. In order to be vulnerable, the application must use Angular SSR, the application must have routes that perform internal redirects, the infrastructure (Reverse Proxy/CDN) must pass the `X-Forwarded-Prefix` header to the SSR process without sanitization, and the cache must not vary on the `X-Forwarded-Prefix` header. Versions 21.2.0-rc.1, 21.1.5, 20.3.17, and 19.2.21 contain a patch. Until the patch is applied, developers should sanitize the `X-Forwarded-Prefix` header in their`server.ts` before the Angular engine processes the request.

Affected Products
Vendor
angular
Product
angular-cli
Versions
Affected
  • >= 21.2.0-next.2, < 21.2.0-rc.0
  • >= 21.0.0-next.0, < 21.1.5
  • >= 20.0.0-next.0, < 20.3.17
  • >= 19.0.0-next.0, < 19.2.21
Problem Types
TypeCWE IDDescription
CWECWE-601CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
Type: CWE
CWE ID: CWE-601
Description: CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
Metrics
VersionBase scoreBase severityVector
4.06.9MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Version: 4.0
Base score: 6.9
Base severity: MEDIUM
Vector:
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Metrics Other Info
Impacts
CAPEC IDDescription
Solutions

Configurations

Workarounds

Exploits

Credits

Timeline
EventDate
Replaced By

Rejected Reason

References
HyperlinkResource
https://github.com/angular/angular-cli/security/advisories/GHSA-xh43-g2fq-wjrj
x_refsource_CONFIRM
https://github.com/angular/angular-cli/issues/32501
x_refsource_MISC
https://github.com/angular/angular-cli/pull/32521
x_refsource_MISC
https://github.com/angular/angular-cli/commit/877f017ace4b83277d773aa37f5813e5e9faec7e
x_refsource_MISC
Hyperlink: https://github.com/angular/angular-cli/security/advisories/GHSA-xh43-g2fq-wjrj
Resource:
x_refsource_CONFIRM
Hyperlink: https://github.com/angular/angular-cli/issues/32501
Resource:
x_refsource_MISC
Hyperlink: https://github.com/angular/angular-cli/pull/32521
Resource:
x_refsource_MISC
Hyperlink: https://github.com/angular/angular-cli/commit/877f017ace4b83277d773aa37f5813e5e9faec7e
Resource:
x_refsource_MISC
▼Authorized Data Publishers (ADP)
CISA ADP Vulnrichment
Affected Products
Metrics
VersionBase scoreBase severityVector
Metrics Other Info
Impacts
CAPEC IDDescription
Solutions

Configurations

Workarounds

Exploits

Credits

Timeline
EventDate
Replaced By

Rejected Reason

References
HyperlinkResource
https://github.com/angular/angular-cli/issues/32501
exploit
Hyperlink: https://github.com/angular/angular-cli/issues/32501
Resource:
exploit
Information is not available yet
▼National Vulnerability Database (NVD)
nvd.nist.gov
Source:security-advisories@github.com
Published At:25 Feb, 2026 | 17:25
Updated At:27 Feb, 2026 | 21:16

The Angular SSR is a server-rise rendering tool for Angular applications. An Open Redirect vulnerability exists in the internal URL processing logic in versions on the 19.x branch prior to 19.2.21, the 20.x branch prior to 20.3.17, and the 21.x branch prior to 21.1.5 and 21.2.0-rc.1. The logic normalizes URL segments by stripping leading slashes; however, it only removes a single leading slash. When an Angular SSR application is deployed behind a proxy that passes the `X-Forwarded-Prefix` header, an attacker can provide a value starting with three slashes. This vulnerability allows attackers to conduct large-scale phishing and SEO hijacking. In order to be vulnerable, the application must use Angular SSR, the application must have routes that perform internal redirects, the infrastructure (Reverse Proxy/CDN) must pass the `X-Forwarded-Prefix` header to the SSR process without sanitization, and the cache must not vary on the `X-Forwarded-Prefix` header. Versions 21.2.0-rc.1, 21.1.5, 20.3.17, and 19.2.21 contain a patch. Until the patch is applied, developers should sanitize the `X-Forwarded-Prefix` header in their`server.ts` before the Angular engine processes the request.

CISA Catalog
Date AddedDue DateVulnerability NameRequired Action
N/A
Date Added: N/A
Due Date: N/A
Vulnerability Name: N/A
Required Action: N/A
Metrics
TypeVersionBase scoreBase severityVector
Secondary4.06.9MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Type: Secondary
Version: 4.0
Base score: 6.9
Base severity: MEDIUM
Vector:
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CPE Matches

Weaknesses
CWE IDTypeSource
CWE-601Secondarysecurity-advisories@github.com
CWE ID: CWE-601
Type: Secondary
Source: security-advisories@github.com
Evaluator Description

Evaluator Impact

Evaluator Solution

Vendor Statements

References
HyperlinkSourceResource
https://github.com/angular/angular-cli/commit/877f017ace4b83277d773aa37f5813e5e9faec7esecurity-advisories@github.com
N/A
https://github.com/angular/angular-cli/issues/32501security-advisories@github.com
N/A
https://github.com/angular/angular-cli/pull/32521security-advisories@github.com
N/A
https://github.com/angular/angular-cli/security/advisories/GHSA-xh43-g2fq-wjrjsecurity-advisories@github.com
N/A
https://github.com/angular/angular-cli/issues/32501134c704f-9b21-4f2e-91b3-4a467353bcc0
N/A
Hyperlink: https://github.com/angular/angular-cli/commit/877f017ace4b83277d773aa37f5813e5e9faec7e
Source: security-advisories@github.com
Resource: N/A
Hyperlink: https://github.com/angular/angular-cli/issues/32501
Source: security-advisories@github.com
Resource: N/A
Hyperlink: https://github.com/angular/angular-cli/pull/32521
Source: security-advisories@github.com
Resource: N/A
Hyperlink: https://github.com/angular/angular-cli/security/advisories/GHSA-xh43-g2fq-wjrj
Source: security-advisories@github.com
Resource: N/A
Hyperlink: https://github.com/angular/angular-cli/issues/32501
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Resource: N/A

Change History

0
Information is not available yet

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2Records found

CVE-2026-33397
Matching Score-10
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ShareView Details
Matching Score-10
Assigner-GitHub, Inc.
CVSS Score-6.9||MEDIUM
EPSS-0.01% / 1.17%
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7 Day CHG-0.04%
Published-26 Mar, 2026 | 13:46
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Angular SSR Vulnerable to Protocol-Relative URL Injection via Single Backslash Bypass

The Angular SSR is a server-rise rendering tool for Angular applications. Versions on the 22.x branch prior to 22.0.0-next.2, the 21.x branch prior to 21.2.3, and the 20.x branch prior to 20.3.21 have an Open Redirect vulnerability in `@angular/ssr` due to an incomplete fix for CVE-2026-27738. While the original fix successfully blocked multiple leading slashes (e.g., `///`), the internal validation logic fails to account for a single backslash (`\`) bypass. When an Angular SSR application is deployed behind a proxy that passes the `X-Forwarded-Prefix` header, an attacker provides a value starting with a single backslash, the internal validation failed to flag the single backslash as invalid, the application prepends a leading forward slash, resulting in a `Location` header containing the URL, and modern browsers interpret the `/\` sequence as `//`, treating it as a protocol-relative URL and redirecting the user to the attacker-controlled domain. Furthermore, the response lacks the `Vary: X-Forwarded-Prefix` header, allowing the malicious redirect to be stored in intermediate caches (Web Cache Poisoning). Versions 22.0.0-next.2, 21.2.3, and 20.3.21 contain a patch. Until the patch is applied, developers should sanitize the `X-Forwarded-Prefix` header in their `server.ts` before the Angular engine processes the request.

Action-Not Available
Vendor-angularangular
Product-angular_cliangular-cli
CWE ID-CWE-601
URL Redirection to Untrusted Site ('Open Redirect')
CVE-2025-27143
Matching Score-4
Assigner-GitHub, Inc.
ShareView Details
Matching Score-4
Assigner-GitHub, Inc.
CVSS Score-6.9||MEDIUM
EPSS-0.21% / 42.29%
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7 Day CHG~0.00%
Published-24 Feb, 2025 | 22:16
Updated-28 Feb, 2025 | 16:07
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Known To Be Used In Ransomware Campaigns?-Not Available
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Beter Auth has an Open Redirect via Scheme-Less Callback Parameter

Better Auth is an authentication and authorization library for TypeScript. Prior to version 1.1.21, the application is vulnerable to an open redirect due to improper validation of the callbackURL parameter in the email verification endpoint and any other endpoint that accepts callback url. While the server blocks fully qualified URLs, it incorrectly allows scheme-less URLs. This results in the browser interpreting the URL as a fully qualified URL, leading to unintended redirection. An attacker can exploit this flaw by crafting a malicious verification link and tricking users into clicking it. Upon successful email verification, the user will be automatically redirected to the attacker's website, which can be used for phishing, malware distribution, or stealing sensitive authentication tokens. This CVE is a bypass of the fix for GHSA-8jhw-6pjj-8723/CVE-2024-56734. Version 1.1.21 contains an updated patch.

Action-Not Available
Vendor-better-authbetter-auth
Product-better_authbetter-auth
CWE ID-CWE-601
URL Redirection to Untrusted Site ('Open Redirect')
Details not found