A vulnerability was found in a way libcurl uses NTLM-authenticated proxy connections.
Libcurl will reuse NTLM-authenticated proxy connections without properly making sure,
that the connection was authenticated with the same credentials as set for this transfer.
Upstream bug report:
Red Hat would like to thank curl upstream for reporting this issue. Upstream acknowledges Isaac Boukris as the original reporter.
Created curl tracking bugs for this issue:
Affects: fedora-all [bug 1302265]
Created mingw-curl tracking bugs for this issue:
Affects: fedora-all [bug 1302264]
Affects: epel-7 [bug 1302266]
curl-7.43.0-5.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.
curl-7.40.0-8.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.
This issue affects use cases when curl uses HTTP proxy with NTLM authentication, and switches to different proxy or different proxy authentication credentials between requests. Later requests may unexpectedly re-use authenticated proxy connections from earlier requests.
Due to this issue being limited to very specific circumstances, there is currently no plan to backport the fix to released Red Hat Enterprise Linux versions.