Privilege Esc Escalation: libcurl Fails to Clear Proxy Auth Credentials
CVE-2026-9079 Published on July 3, 2026
stale proxy password leak
libcurl had a flaw that when instructed to clear proxy authentication
credentials which made it not do so, leaving the old credentials around to get
used for subsequent transfers that should not know nor use them.
Vulnerability Analysis
CVE-2026-9079 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. An automatable proof of concept (POC) exploit exists. The potential impact of an exploit of this vulnerability is considered to be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.
Products Associated with CVE-2026-9079
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Affected Versions
curl:- Version 8.20.0, <= 8.20.0 is affected.
- Version 8.19.0, <= 8.19.0 is affected.
- Version 8.18.0, <= 8.18.0 is affected.
- Version 8.17.0, <= 8.17.0 is affected.
- Version 8.16.0, <= 8.16.0 is affected.
- Version 8.15.0, <= 8.15.0 is affected.
- Version 8.14.1, <= 8.14.1 is affected.
- Version 8.14.0, <= 8.14.0 is affected.
- Version 8.13.0, <= 8.13.0 is affected.
- Version 8.12.1, <= 8.12.1 is affected.
- Version 8.12.0, <= 8.12.0 is affected.
- Version 8.11.1, <= 8.11.1 is affected.
- Version 8.11.0, <= 8.11.0 is affected.
- Version 8.10.1, <= 8.10.1 is affected.
- Version 8.10.0, <= 8.10.0 is affected.
- Version 8.9.1, <= 8.9.1 is affected.
- Version 8.9.0, <= 8.9.0 is affected.
- Version 8.8.0, <= 8.8.0 is affected.