High severity · published Jan 6, 2025
CVE-2025-21620
Deno's authorization headers not dropped when redirecting cross-origin
7.5
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DE
deno · denoland
< 2.1.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-21620
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-21620
github.com
https://github.com/denoland/deno/security/advisories/GHSA-f27p-cmv8-xhm6
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