CVE-2021-22876

Publication date 31 March 2021

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

curl 7.1.1 to and including 7.75.0 is vulnerable to an "Exposure of Private Personal Information to an Unauthorized Actor" by leaking credentials in the HTTP Referer: header. libcurl does not strip off user credentials from the URL when automatically populating the Referer: HTTP request header field in outgoing HTTP requests, and therefore risks leaking sensitive data to the server that is the target of the second HTTP request.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
curl	21.04 hirsute	Fixed 7.74.0-1ubuntu2
	20.10 groovy	Fixed 7.68.0-1ubuntu4.3
	20.04 LTS focal	Fixed 7.68.0-1ubuntu2.5
	18.04 LTS bionic	Fixed 7.58.0-2ubuntu3.13
	16.04 LTS xenial	Fixed 7.47.0-1ubuntu2.19
	14.04 LTS trusty	Fixed 7.35.0-1ubuntu2.20+esm7

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Notes

alexmurray

affects curl versions between 7.1.1 and 7.75.0

Patch details

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

Package	Patch details
curl	Vendor: https://curl.se/XOXep4o2CSG0.patch

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