CVE-2026-3783

NameCVE-2026-3783
DescriptionWhen 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.
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
curl (PTS)bullseye7.74.0-1.3+deb11u13vulnerable
bullseye (security)7.74.0-1.3+deb11u16vulnerable
bookworm7.88.1-10+deb12u14vulnerable
bookworm (security)7.88.1-10+deb12u5vulnerable
trixie8.14.1-2+deb13u2vulnerable
forky8.19.0-1fixed
sid8.19.0-3fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
curlsource(unstable)8.19.0-1

Notes

[trixie] - curl <no-dsa> (Minor issue)
[bookworm] - curl <no-dsa> (Minor issue)
[bullseye] - curl <postponed> (Minor issue)
https://curl.se/docs/CVE-2026-3783.html
Introduced with: https://github.com/curl/curl/commit/06c1bea72faabb6fad4b7ef818aafaa336c9a7aa (curl-7_33_0)
Fixed by: https://github.com/curl/curl/commit/e3d7401a32a46516c9e5ee877e613e62ed35bddc (curl-8_19_0)

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