CVE-2026-3783

Publication date 11 March 2026

Last updated 13 March 2026

Ubuntu priority

Cvss 3 Severity Score

Description

When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a redirect to a second URL, curl cwould leak that token to the second hostname under some circumstances.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
curl	25.10 questing	Fixed 8.14.1-2ubuntu1.2
	24.04 LTS noble	Fixed 8.5.0-2ubuntu10.8
	22.04 LTS jammy	Fixed 7.81.0-1ubuntu1.23
	20.04 LTS focal	Vulnerable
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Notes

john-breton

The HTTP Bearer authentication feature was not added into cURL until 7.61.0. Anything older than that is not vulnerable.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
curl	Upstream: e3d7401

Severity score breakdown

Parameter	Value
Base score	5.3 · Medium
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	Low
Integrity impact	None
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

References

Related Ubuntu Security Notices (USN)

USN-8084-1
curl vulnerabilities
11 March 2026