CVE-2026-3783

token leak with redirect and netrc

Published Mar 11, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer
performs a redirect to a second URL, curl could leak that token to the second
hostname under some circumstances.

If the hostname that the first request is redirected to has information in the
used .netrc file, with either of the `machine` or `default` keywords, curl
would pass on the bearer token set for the first host also to the second one.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Ubuntu USN Ubuntu USN USN-8084-1 curl vulnerabilities
Ubuntu USN Ubuntu USN USN-8099-1 curl vulnerabilities
History
Type Values Removed Values Added
First Time appeared Haxx
Haxx curl
CPEs cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*
Vendors & Products Haxx
Haxx curl
Type Values Removed Values Added
First Time appeared Curl
Curl curl
Vendors & Products Curl
Curl curl
Type Values Removed Values Added
Weaknesses CWE-522
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a redirect to a second URL, curl could leak that token to the second hostname under some circumstances. If the hostname that the first request is redirected to has information in the used .netrc file, with either of the `machine` or `default` keywords, curl would pass on the bearer token set for the first host also to the second one.
Title token leak with redirect and netrc
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
curl
Published
Updated
Sep 15, 2026, 6:02 AM
Reserved
Mar 8, 2026, 5:09 AM
Status
Modified
Published
Mar 11, 2026, 11:16 AM
Modified
Sep 15, 2026, 7:16 AM
Severity
Moderate
Public date
Mar 11, 2026, 10:09 AM