go-git: Improper Link Resolution Before File Access
CVE-2026-71556 is a high-severity improper link resolution before file access vulnerability in go-git, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected go-git versions: < 5.19.2; >= 6.0.0-alpha.1, < 6.0.0-alpha.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of go-git you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Go-git | go-git | < 5.19.2; >= 6.0.0-alpha.1, < 6.0.0-alpha.5 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L. Scored by CNA (github.com).
Official description
go-git is an extensible git implementation library written in pure Go. Prior to 5.19.2 and 6.0.0-alpha.5, worktree operations (including checkout, status, and add) resolve symbolic links inside the working tree without confining resolution to the worktree boundary, so a maliciously crafted repository containing a symlink can cause go-git to read from or write to files outside the intended working directory when the repository is cloned and its worktree operations are used. Versions 5.19.2 and 6.0.0-alpha.5.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Link Resolution Before File Access
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
How developers prevent this class of flaw
- Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.
More Improper Link Resolution Before File Access vulnerabilities (CWE-59)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in go-git
- 9.6 Critical severity
- 7.5 High severity
- 7.4 High severity
- 7.5 High severity
- 9.2 Critical severity
- 9.8 Critical severity
Recent Improper Link Resolution Before File Access vulnerabilities
- 9.1 Critical severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 9.2 Critical severity
- 7.5 High severity
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