Removing sensitive data from a repository
If you commit sensitive data, such as a password or SSH key into a Git repository, you can remove it from the history. To entirely remove unwanted files from a repository's history you can use either the
git filter-branch command or the BFG Repo-Cleaner open source tool.
In this article
- Purging a file from your repository's history
- Avoiding accidental commits in the future
- Further reading
git filter-branch command and the BFG Repo-Cleaner rewrite your repository's history, which changes the SHAs for existing commits that you alter and any dependent commits. Changed commit SHAs may affect open pull requests in your repository. We recommend merging or closing all open pull requests before removing files from your repository.
You can remove the file from the latest commit with
git rm. For information on removing a file that was added with the latest commit, see "Removing files from a repository's history."
Warning: Once you have pushed a commit to GitHub, you should consider any data it contains to be compromised. If you committed a password, change it! If you committed a key, generate a new one.
This article tells you how to make commits with sensitive data unreachable from any branches or tags in your GitHub repository. However, it's important to note that those commits may still be accessible in any clones or forks of your repository, directly via their SHA-1 hashes in cached views on GitHub, and through any pull requests that reference them. You can't do anything about existing clones or forks of your repository, but you can permanently remove cached views and references to the sensitive data in pull requests on GitHub by contacting GitHub Support or GitHub Premium Support.
Purging a file from your repository's history
Using the BFG
The BFG Repo-Cleaner is a tool that's built and maintained by the open source community. It provides a faster, simpler alternative to
git filter-branch for removing unwanted data. For example, to remove your file with sensitive data and leave your latest commit untouched, run:
$ bfg --delete-files YOUR-FILE-WITH-SENSITIVE-DATA
To replace all text listed in
passwords.txt wherever it can be found in your repository's history, run:
$ bfg --replace-text passwords.txt
See the BFG Repo-Cleaner's documentation for full usage and download instructions.
Warning: If you run
git filter-branch after stashing changes, you won't be able to retrieve your changes with other stash commands. Before running
git filter-branch, we recommend unstashing any changes you've made. To unstash the last set of changes you've stashed, run
git stash show -p | git apply -R. For more information, see Git Tools Stashing.
To illustrate how
git filter-branch works, we'll show you how to remove your file with sensitive data from the history of your repository and add it to
.gitignore to ensure that it is not accidentally re-committed.
If you don't already have a local copy of your repository with sensitive data in its history, clone the repository to your local computer.
$ git clone https://github.com/YOUR-USERNAME/YOUR-REPOSITORY > Initialized empty Git repository in /Users/YOUR-FILE-PATH/YOUR-REPOSITORY/.git/ > remote: Counting objects: 1301, done. > remote: Compressing objects: 100% (769/769), done. > remote: Total 1301 (delta 724), reused 910 (delta 522) > Receiving objects: 100% (1301/1301), 164.39 KiB, done. > Resolving deltas: 100% (724/724), done.
Navigate into the repository's working directory.
$ cd YOUR-REPOSITORY
Run the following command, replacing
PATH-TO-YOUR-FILE-WITH-SENSITIVE-DATAwith the path to the file you want to remove, not just its filename. These arguments will:
- Force Git to process, but not check out, the entire history of every branch and tag
- Remove the specified file, as well as any empty commits generated as a result
Overwrite your existing tags
$ git filter-branch --force --index-filter \ "git rm --cached --ignore-unmatch PATH-TO-YOUR-FILE-WITH-SENSITIVE-DATA" \ --prune-empty --tag-name-filter cat -- --all > Rewrite 48dc599c80e20527ed902928085e7861e6b3cbe6 (266/266) > Ref 'refs/heads/master' was rewritten
Note: If the file with sensitive data used to exist at any other paths (because it was moved or renamed), you must run this command on those paths, as well.
Add your file with sensitive data to
.gitignoreto ensure that you don't accidentally commit it again.
$ echo "YOUR-FILE-WITH-SENSITIVE-DATA" >> .gitignore $ git add .gitignore $ git commit -m "Add YOUR-FILE-WITH-SENSITIVE-DATA to .gitignore" > [master 051452f] Add YOUR-FILE-WITH-SENSITIVE-DATA to .gitignore > 1 files changed, 1 insertions(+), 0 deletions(-)
Double-check that you've removed everything you wanted to from your repository's history, and that all of your branches are checked out.
Once you're happy with the state of your repository, force-push your local changes to overwrite your GitHub repository, as well as all the branches you've pushed up:
$ git push origin --force --all > Counting objects: 1074, done. > Delta compression using 2 threads. > Compressing objects: 100% (677/677), done. > Writing objects: 100% (1058/1058), 148.85 KiB, done. > Total 1058 (delta 590), reused 602 (delta 378) > To https://github.com/YOUR-USERNAME/YOUR-REPOSITORY.git > + 48dc599...051452f master -> master (forced update)
In order to remove the sensitive file from your tagged releases, you'll also need to force-push against your Git tags:
$ git push origin --force --tags > Counting objects: 321, done. > Delta compression using up to 8 threads. > Compressing objects: 100% (166/166), done. > Writing objects: 100% (321/321), 331.74 KiB | 0 bytes/s, done. > Total 321 (delta 124), reused 269 (delta 108) > To https://github.com/YOUR-USERNAME/YOUR-REPOSITORY.git > + 48dc599...051452f master -> master (forced update)
Contact GitHub Support or GitHub Premium Support, asking them to remove cached views and references to the sensitive data in pull requests on GitHub.
Tell your collaborators to rebase, not merge, any branches they created off of your old (tainted) repository history. One merge commit could reintroduce some or all of the tainted history that you just went to the trouble of purging.
After some time has passed and you're confident that
git filter-branchhad no unintended side effects, you can force all objects in your local repository to be dereferenced and garbage collected with the following commands (using Git 1.8.5 or newer):
$ git for-each-ref --format="delete %(refname)" refs/original | git update-ref --stdin $ git reflog expire --expire=now --all $ git gc --prune=now > Counting objects: 2437, done. > Delta compression using up to 4 threads. > Compressing objects: 100% (1378/1378), done. > Writing objects: 100% (2437/2437), done. > Total 2437 (delta 1461), reused 1802 (delta 1048)
Note: You can also achieve this by pushing your filtered history to a new or empty repository and then making a fresh clone from GitHub.
Avoiding accidental commits in the future
There are a few simple tricks to avoid committing things you don't want committed:
- Use a visual program like GitHub Desktop or gitk to commit changes. Visual programs generally make it easier to see exactly which files will be added, deleted, and modified with each commit.
- Avoid the catch-all commands
git add .and
git commit -aon the command line—use
git add filenameand
git rm filenameto individually stage files, instead.
git add --interactiveto individually review and stage changes within each file.
git diff --cachedto review the changes that you have staged for commit. This is the exact diff that
git commitwill produce as long as you don't use the