CVE-2025-21620 - CVE House
Back to Database
Status published High CVE-2025-21620

Deno's authorization headers not dropped when redirecting cross-origin

Vulnerability Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. When you send a request with the Authorization header to one domain, and the response asks to redirect to a different domain, Deno'sfetch() redirect handling creates a follow-up redirect request that keeps the original Authorization header, leaking its content to that second domain. This vulnerability is fixed in 2.1.2.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2025-21620

Credits & Attribution

No credits recorded in the NVD database.

References

More from denoland

View All →
CVE-2025-61787
Deno is Vulnerable to Command Injection on Windows During Batch File Execution
High 8.1
CVE-2025-61786
Deno's --deny-read check does not prevent permission bypass
Low 3.3
CVE-2025-61785
Deno's --deny-write check does not prevent permission bypass
Low 3.3
CVE-2025-55195
@std/toml Prototype Pollution in Node.js and Browser
High 7.3
CVE-2025-48935
Deno has --allow-read / --allow-write permission bypass in `node:sqlite`
Medium 5.5

Affected Vendor

Affected Software

deno
Vulnerable Versions:
< 2.1.2

Timeline

Official Publish: January 6th, 2025
Last Modified: January 7th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Weaknesses (CWE)

CWE-200

MITRE ATT&CK TTPs

T1213 Data from Information Repositories
Collection
T1005 Data from Local System
Collection
T1552 Unsecured Credentials
Credential Access
T1041 Exfiltration Over C2 Channel
Exfiltration