Certificate Verification Failed "unknown certificate lookup failure"

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#2,096 opened on May 23, 2024 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 4/5
Estimated time: 3-5 days
Newbie friendliness: 35/100

Issue type: Bug
Clarity: Needs clarification
Activity status: Stale
Tech stack: csharp, git
Domain: devtools, security

Research direction

Start at the Repository.Clone API and compare certificate-verification behavior between libgit2sharp v0.26.2 and v0.30.0. Reproduce the failure on Windows 11 with .NET Framework 4.7.2 in the affected environment; done means the internal repository can be cloned without the SSL/TLS verification error.

Written by the indexing model from the issue text.

Description

I recently updated libgit2sharp (v0.26.2) to the latest v0.30.0.

Some of my product users are located in Taiwan, some are in China, and some are from Europe and the United States.

Before the upgrade, the company's internal repository could be accessed normally through the Repository.Clone API.
(URL and WorkDir only, no other options)

After the upgrade, users located in China will fail and get an error about SSL/TLS being unable to verify, as shown below.

We tried to troubleshoot other network issues and confirmed that all users were on the same OS version and supported TLS 1.2/1.3 only.

And do cross comparison with git CLI (git v2.43.0).

Everyone can download normally through the CLI, and will not encounter SSL/TLS verification errors when using libgit2sharp v0.26.2.

Only users located in China will encounter SSL/TLS verification failure in libgit2sharp v0.30.0.

Version of LibGit2Sharp (release number or SHA1)

v0.30.0

Operating system(s) tested; .NET runtime tested

Windows11
OS Build 22631.3593
Windows Feature Experience Pack 1000.22700.1003.0

.NET Framework 4.7.2

Dominant language: C#
Stars: 3.5k
Forks: 925
PR merge metrics: No merged PRs in 30d

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First steps

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