CVE-2026-41506: go-git credential leak via cross-host redirect in smart HTTP transport

CVE-2026-41506 · Severity: medium · CVSS 4.7 · Published 2026-05-08

go-git is a library used by developers to integrate Git functionality into Go applications. A security flaw allows sensitive login credentials to be leaked to unauthorized third-party servers when the library follows a web redirect during repository operations. This could allow an attacker who controls a malicious Git server to steal user credentials and gain unauthorized access to other private repositories or resources.

Technologies: github.com/go-git/go-git/v5 (Go), github.com/go-git/go-git/v6 (Go), Go-Git. Vendors: Go, Go-Git.

Quick answers

Is CVE-2026-41506 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-41506 being exploited in the wild.
How severe is CVE-2026-41506?
Medium severity, with a CVSS score of 4.7, published 8 May 2026.
Which products and versions are affected?
github.com/go-git/go-git/v5 (Go) <= 5.17.2, SEMVER:introduced=0,fixed=5.18.0; github.com/go-git/go-git/v6 (Go) <= 6.0.0-alpha.1, SEMVER:introduced=0,fixed=6.0.0-alpha.2; Go-Git < 5.18.0.
Is there a fix for CVE-2026-41506?
Yes. github.com/go-git/go-git/v5 (Go): upgrade to 5.18.0 or later; github.com/go-git/go-git/v6 (Go): upgrade to 6.0.0-alpha.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-41506 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-41506?
Check whether you run github.com/go-git/go-git/v5 (Go), github.com/go-git/go-git/v6 (Go) or Go-Git at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/go-git/go-git/v5 (Go): upgrade to 5.18.0 or later
    go get github.com/go-git/go-git/v5@v5.18.0
  • github.com/go-git/go-git/v6 (Go): upgrade to 6.0.0-alpha.2 or later
    go get github.com/go-git/go-git/v6@v6.0.0-alpha.2

Technical details

A credential leak vulnerability exists in go-git's smart-HTTP transport implementation. When a remote repository responds to an initial /info/refs request with a redirect to a different host, go-git updates the session endpoint to the new location but reuses the original Authorization headers for subsequent requests. This allows an attacker-controlled server to capture credentials intended for the original host. The vulnerability is rooted in insufficient protection of credentials during cross-host redirects (CWE-522). The issue is addressed in versions 5.18.0 and 6.0.0-alpha.2 by introducing a configurable followRedirects policy that defaults to 'initial' only, matching canonical Git behavior.

Affected products

  • go-git go-git/v5 < 5.18.0
  • go-git go-git/v6 < 6.0.0-alpha.2

Identifiers

  • CVE-2026-41506
  • GHSA-3xc5-wrhm-f963
  • GO-2026-5105

Timeline

  • 2026-04-16: patched: Versions 5.18.0 and 6.0.0-alpha.2 released
  • 2026-05-08: disclosed: Initial CVE publication
  • 2026-05-08: advisory: GitHub Security Advisory published

References

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