OAuth2 Bearer Token Vulnerability in cURL
CVE-2025-14524

5.3MEDIUM

Key Information:

Vendor

Curl

Status
Curl
Vendor
CVE Published:
8 January 2026

What is CVE-2025-14524?

A vulnerability exists in cURL where the application improperly handles OAuth2 bearer tokens during HTTP(S) transfers. When a cross-protocol redirect occurs to a second URL using protocols like IMAP, LDAP, POP3, or SMTP, cURL may inadvertently send the bearer token to the new target host. This could potentially allow unauthorized access to sensitive information or data. Users are advised to implement protective measures to safeguard their tokens during HTTP(S) interactions.

Affected Version(s)

curl 8.17.0

curl 8.16.0

curl 8.15.0

References

https://curl.se/docs/CVE-2025-14524.json
https://curl.se/docs/CVE-2025-14524.html
https://hackerone.com/reports/3459417

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

anonymous237 on hackerone
Daniel Stenberg
.