go-git is an extensible git implementation library written in pure Go. Prior to 5.19.0 and 6.0.0-alpha.3, go-git may parse malformed Git objects in a way that differs from upstream Git. When commit or tag objects contain ambiguous or malformed headers, go-git’s decoded representation may expose values differently from how Git itself would interpret or reject the same object. Additionally, go-git’s commit signing and verification logic operates over commit data reconstructed from go-git’s parsed representation rather than the original raw object bytes. As a result, go-git may sign or verify a commit payload that is not byte-for-byte equivalent to the object stored in the repository. This can cause a signature to appear valid for a commit whose displayed or effective metadata differs from the object that was intended to be signed. This vulnerability is fixed in 5.19.0 and 6.0.0-alpha.3.
go-git is an extensible git implementation library written in pure Go. Prior to 5.19.0 and 6.0.0-alpha.3, go-git may parse malformed Git objects in a way that differs from upstream Git. When commit or tag objects contain ambiguous or malformed headers, go-git’s decoded representation may expose values differently from how Git itself would interpret or reject the same object. Additionally, go-git’s commit signing and verification logic operates over commit data reconstructed from go-git’s parsed representation rather than the original raw object bytes. As a result, go-git may sign or verify a commit payload that is not byte-for-byte equivalent to the object stored in the repository. This can cause a signature to appear valid for a commit whose displayed or effective metadata differs from the object that was intended to be signed. This vulnerability is fixed in 5.19.0 and 6.0.0-alpha.3.
go-git is an extensible git implementation library written in pure Go. Prior to 5.19.0 and 6.0.0-alpha.3, go-git may parse malformed Git objects in a way that differs from upstream Git. When commit or tag objects contain ambiguous or malformed headers, go-git’s decoded representation may expose values differently from how Git itself would interpret or reject the same object. Additionally, go-git’s commit signing and verification logic operates over commit data reconstructed from go-git’s parsed representation rather than the original raw object bytes. As a result, go-git may sign or verify a commit payload that is not byte-for-byte equivalent to the object stored in the repository. This can cause a signature to appear valid for a commit whose displayed or effective metadata differs from the object that was intended to be signed. This vulnerability is fixed in 5.19.0 and 6.0.0-alpha.3.
### Impact
`go-git` may parse malformed Git objects in a way that differs from upstream Git. When `commit` or `tag` objects contain ambiguous or malformed headers, `go-git`’s decoded representation may expose values differently from how Git itself would interpret or reject the same object.
Additionally, `go-git`’s commit signing and verification logic operates over commit data reconstructed from `go-git`’s parsed representation rather than the original raw object bytes. As a result, `go-git` may sign or verify a commit payload that is not byte-for-byte equivalent to the object stored in the repository.
This can cause a signature to appear valid for a commit whose displayed or effective metadata differs from the object that was intended to be signed.
### Patches
Users should upgrade to a patched version in order to mitigate this vulnerability. Versions prior to v5 are likely to be affected, users are recommended to upgrade to a supported `go-git` version.
### Credit
Thanks to @bugbunny-research (https://bugbunny.ai/) for reporting this to `sigstore/gitsign`, and to @wlynch, @patzielinski and @adityasaky for coordinating the disclosure with the `go-git` project. :bow: :1st_place_medal:
Thanks to @wayphinder for reporting this to the `go-git` project. :bow:
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
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datePublished: May 27, 2026, 2:54:47 PM
dateUpdated: May 27, 2026, 3:43:32 PM
1 related source bulletins · separate from aliases
openSUSE-SU-2026:10769-1: flux2-cli-2.8.7-1.1 on GA media
CVE-2026-45022
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NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
The original JSON retains the logical configuration operators, exclusions and version bounds.
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.