CURL: Improper HTTP Proxy Connection Reuse with Different Credentials
CVE-2026-3784 Published on March 11, 2026
wrong proxy connection reuse with credentials
curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a
server, even if the new request uses different credentials for the HTTP proxy.
The proper behavior is to create or use a separate connection.
Vulnerability Analysis
CVE-2026-3784 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality and integrity, and no impact on availability.
Weakness Type
Authentication Bypass by Primary Weakness
The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error.
Products Associated with CVE-2026-3784
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Affected Versions
curl:- 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.
- Version 8.7.1, <= 8.7.1 is affected.
- Version 8.7.0, <= 8.7.0 is affected.
- Version 8.6.0, <= 8.6.0 is affected.
- Version 8.5.0, <= 8.5.0 is affected.
- Version 8.4.0, <= 8.4.0 is affected.
- Version 8.3.0, <= 8.3.0 is affected.
- Version 8.2.1, <= 8.2.1 is affected.
- Version 8.2.0, <= 8.2.0 is affected.
- Version 8.1.2, <= 8.1.2 is affected.
- Version 8.1.1, <= 8.1.1 is affected.
- Version 8.1.0, <= 8.1.0 is affected.
- Version 8.0.1, <= 8.0.1 is affected.
- Version 8.0.0, <= 8.0.0 is affected.
- Version 7.88.1, <= 7.88.1 is affected.
- Version 7.88.0, <= 7.88.0 is affected.
- Version 7.87.0, <= 7.87.0 is affected.
- Version 7.86.0, <= 7.86.0 is affected.
- Version 7.85.0, <= 7.85.0 is affected.
- Version 7.84.0, <= 7.84.0 is affected.
- Version 7.83.1, <= 7.83.1 is affected.
- Version 7.83.0, <= 7.83.0 is affected.
- Version 7.82.0, <= 7.82.0 is affected.
- Version 7.81.0, <= 7.81.0 is affected.
- Version 7.80.0, <= 7.80.0 is affected.
- Version 7.79.1, <= 7.79.1 is affected.
- Version 7.79.0, <= 7.79.0 is affected.
- Version 7.78.0, <= 7.78.0 is affected.
- Version 7.77.0, <= 7.77.0 is affected.
- Version 7.76.1, <= 7.76.1 is affected.
- Version 7.76.0, <= 7.76.0 is affected.
- Version 7.75.0, <= 7.75.0 is affected.
- Version 7.74.0, <= 7.74.0 is affected.
- Version 7.73.0, <= 7.73.0 is affected.
- Version 7.72.0, <= 7.72.0 is affected.
- Version 7.71.1, <= 7.71.1 is affected.
- Version 7.71.0, <= 7.71.0 is affected.
- Version 7.70.0, <= 7.70.0 is affected.
- Version 7.69.1, <= 7.69.1 is affected.
- Version 7.69.0, <= 7.69.0 is affected.
- Version 7.68.0, <= 7.68.0 is affected.
- Version 7.67.0, <= 7.67.0 is affected.
- Version 7.66.0, <= 7.66.0 is affected.
- Version 7.65.3, <= 7.65.3 is affected.
- Version 7.65.2, <= 7.65.2 is affected.
- Version 7.65.1, <= 7.65.1 is affected.
- Version 7.65.0, <= 7.65.0 is affected.
- Version 7.64.1, <= 7.64.1 is affected.
- Version 7.64.0, <= 7.64.0 is affected.
- Version 7.63.0, <= 7.63.0 is affected.
- Version 7.62.0, <= 7.62.0 is affected.
- Version 7.61.1, <= 7.61.1 is affected.
- Version 7.61.0, <= 7.61.0 is affected.
- Version 7.60.0, <= 7.60.0 is affected.
- Version 7.59.0, <= 7.59.0 is affected.
- Version 7.58.0, <= 7.58.0 is affected.
- Version 7.57.0, <= 7.57.0 is affected.
- Version 7.56.1, <= 7.56.1 is affected.
- Version 7.56.0, <= 7.56.0 is affected.
- Version 7.55.1, <= 7.55.1 is affected.
- Version 7.55.0, <= 7.55.0 is affected.
- Version 7.54.1, <= 7.54.1 is affected.
- Version 7.54.0, <= 7.54.0 is affected.
- Version 7.53.1, <= 7.53.1 is affected.
- Version 7.53.0, <= 7.53.0 is affected.
- Version 7.52.1, <= 7.52.1 is affected.
- Version 7.52.0, <= 7.52.0 is affected.
- Version 7.51.0, <= 7.51.0 is affected.
- Version 7.50.3, <= 7.50.3 is affected.
- Version 7.50.2, <= 7.50.2 is affected.
- Version 7.50.1, <= 7.50.1 is affected.
- Version 7.50.0, <= 7.50.0 is affected.
- Version 7.49.1, <= 7.49.1 is affected.
- Version 7.49.0, <= 7.49.0 is affected.
- Version 7.48.0, <= 7.48.0 is affected.
- Version 7.47.1, <= 7.47.1 is affected.
- Version 7.47.0, <= 7.47.0 is affected.
- Version 7.46.0, <= 7.46.0 is affected.
- Version 7.45.0, <= 7.45.0 is affected.
- Version 7.44.0, <= 7.44.0 is affected.
- Version 7.43.0, <= 7.43.0 is affected.
- Version 7.42.1, <= 7.42.1 is affected.
- Version 7.42.0, <= 7.42.0 is affected.
- Version 7.41.0, <= 7.41.0 is affected.
- Version 7.40.0, <= 7.40.0 is affected.
- Version 7.39.0, <= 7.39.0 is affected.
- Version 7.38.0, <= 7.38.0 is affected.
- Version 7.37.1, <= 7.37.1 is affected.
- Version 7.37.0, <= 7.37.0 is affected.
- Version 7.36.0, <= 7.36.0 is affected.
- Version 7.35.0, <= 7.35.0 is affected.
- Version 7.34.0, <= 7.34.0 is affected.
- Version 7.33.0, <= 7.33.0 is affected.
- Version 7.32.0, <= 7.32.0 is affected.
- Version 7.31.0, <= 7.31.0 is affected.
- Version 7.30.0, <= 7.30.0 is affected.
- Version 7.29.0, <= 7.29.0 is affected.
- Version 7.28.1, <= 7.28.1 is affected.
- Version 7.28.0, <= 7.28.0 is affected.
- Version 7.27.0, <= 7.27.0 is affected.
- Version 7.26.0, <= 7.26.0 is affected.
- Version 7.25.0, <= 7.25.0 is affected.
- Version 7.24.0, <= 7.24.0 is affected.
- Version 7.23.1, <= 7.23.1 is affected.
- Version 7.23.0, <= 7.23.0 is affected.
- Version 7.22.0, <= 7.22.0 is affected.
- Version 7.21.7, <= 7.21.7 is affected.
- Version 7.21.6, <= 7.21.6 is affected.
- Version 7.21.5, <= 7.21.5 is affected.
- Version 7.21.4, <= 7.21.4 is affected.
- Version 7.21.3, <= 7.21.3 is affected.
- Version 7.21.2, <= 7.21.2 is affected.
- Version 7.21.1, <= 7.21.1 is affected.
- Version 7.21.0, <= 7.21.0 is affected.
- Version 7.20.1, <= 7.20.1 is affected.
- Version 7.20.0, <= 7.20.0 is affected.
- Version 7.19.7, <= 7.19.7 is affected.
- Version 7.19.6, <= 7.19.6 is affected.
- Version 7.19.5, <= 7.19.5 is affected.
- Version 7.19.4, <= 7.19.4 is affected.
- Version 7.19.3, <= 7.19.3 is affected.
- Version 7.19.2, <= 7.19.2 is affected.
- Version 7.19.1, <= 7.19.1 is affected.
- Version 7.19.0, <= 7.19.0 is affected.
- Version 7.18.2, <= 7.18.2 is affected.
- Version 7.18.1, <= 7.18.1 is affected.
- Version 7.18.0, <= 7.18.0 is affected.
- Version 7.17.1, <= 7.17.1 is affected.
- Version 7.17.0, <= 7.17.0 is affected.
- Version 7.16.4, <= 7.16.4 is affected.
- Version 7.16.3, <= 7.16.3 is affected.
- Version 7.16.2, <= 7.16.2 is affected.
- Version 7.16.1, <= 7.16.1 is affected.
- Version 7.16.0, <= 7.16.0 is affected.
- Version 7.15.5, <= 7.15.5 is affected.
- Version 7.15.4, <= 7.15.4 is affected.
- Version 7.15.3, <= 7.15.3 is affected.
- Version 7.15.2, <= 7.15.2 is affected.
- Version 7.15.1, <= 7.15.1 is affected.
- Version 7.15.0, <= 7.15.0 is affected.
- Version 7.14.1, <= 7.14.1 is affected.
- Version 7.14.0, <= 7.14.0 is affected.
- Version 7.13.2, <= 7.13.2 is affected.
- Version 7.13.1, <= 7.13.1 is affected.
- Version 7.13.0, <= 7.13.0 is affected.
- Version 7.12.3, <= 7.12.3 is affected.
- Version 7.12.2, <= 7.12.2 is affected.
- Version 7.12.1, <= 7.12.1 is affected.
- Version 7.12.0, <= 7.12.0 is affected.
- Version 7.11.2, <= 7.11.2 is affected.
- Version 7.11.1, <= 7.11.1 is affected.
- Version 7.11.0, <= 7.11.0 is affected.
- Version 7.10.8, <= 7.10.8 is affected.
- Version 7.10.7, <= 7.10.7 is affected.
- Version 7.10.6, <= 7.10.6 is affected.
- Version 7.10.5, <= 7.10.5 is affected.
- Version 7.10.4, <= 7.10.4 is affected.
- Version 7.10.3, <= 7.10.3 is affected.
- Version 7.10.2, <= 7.10.2 is affected.
- Version 7.10.1, <= 7.10.1 is affected.
- Version 7.10, <= 7.10 is affected.
- Version 7.9.8, <= 7.9.8 is affected.
- Version 7.9.7, <= 7.9.7 is affected.
- Version 7.9.6, <= 7.9.6 is affected.
- Version 7.9.5, <= 7.9.5 is affected.
- Version 7.9.4, <= 7.9.4 is affected.
- Version 7.9.3, <= 7.9.3 is affected.
- Version 7.9.2, <= 7.9.2 is affected.
- Version 7.9.1, <= 7.9.1 is affected.
- Version 7.9, <= 7.9 is affected.
- Version 7.8.1, <= 7.8.1 is affected.
- Version 7.8, <= 7.8 is affected.
- Version 7.7.3, <= 7.7.3 is affected.
- Version 7.7.2, <= 7.7.2 is affected.
- Version 7.7.1, <= 7.7.1 is affected.
- Version 7.7, <= 7.7 is affected.