GHSA-fj7f-vq84-fh43 · 深刻度： medium · エコシステム： rubygems — Local Code Execution through Argument Injection via dash leading git url parameter in Gemfile.
`Bundler` is a package for managing application dependencies in Ruby. In `bundler` versions before 2.2.33, when working with untrusted and apparently harmless `Gemfile`'s, it is not expected that they lead to execution of external code, unless that's explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile` includes `gem` entries that use the `git` option with invalid, but seemingly harmless, values with a leading dash, this can be false. To handle dependencies that come from a Git repository instead of a registry, Bundler uses various commands, such as `git clone`. These commands are being constructed using user input (e.g. the repository URL). When building the commands, Bundler versions before 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of arguments instead of a command string. However, there is the possibility that a user input starts with a dash (`-`) and is therefore treated as an optional argument instead of a positional one. This can lead to Code Execution because some of the commands have options that can be leveraged to run arbitrary executables. Since this value comes from the `Gemfile` file, it can contain any character, including a leading dash. To exploit this vulnerability, an attacker has to craft a directory containing a `Gemfile` file that declares a dependency that is located in a Git repository. This dependency has to have a Git URL in the form of `-u./payload`. This URL will be used to construct a Git clone command but will be interpreted as the upload-pack argument. Then this directory needs to be shared with the victim, who then needs to run a command that evaluates the Gemfile, such as `bundle lock`, inside. This vulnerability can lead to Arbitrary Code Execution, which could potentially lead to the takeover of the system. However, the exploitability is very low, because it requires a lot of user interaction. Bundler 2.2.33 has patched this problem by inserting `--` as an argument before any positional arguments to those Git commands that were affected by this issue. Regardless of whether users can upgrade or not, they should review any untrustred `Gemfile`'s before running any `bundler` commands that may read them, since they can contain arbitrary ruby code.
総合評価: CVE-2021-43809 は悪用リスクが高い（72.6/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 2.80%、85 パーセンタイル） 根拠: 公開エクスプロイトが 2 件参照されています（Exploit-DB）。 直近 1 日で EPSS が +1.24% 上昇。悪用への関心が高まっている可能性があります。 推奨対応: 公開エクスプロイトが確認されています。影響範囲の確認、緩和策の適用、パッチ適用を優先してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
| EDB-ID | ソース | 種別 | 公開 | リンク |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ | |
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置（高いほど相対的に深刻）を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ（新 − 旧） |
|---|---|---|---|---|
| 1 | 2026-06-15 | 1.55% | 2.80% | +1.24% |
| 2 | 2026-04-24 | 1.32% | 1.55% | +0.23% |
| 3 | 2026-04-19 | — | 1.32% | — |
EPSS の全履歴 （全 31 件）
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 6.7 | 3.1 | MEDIUM |
|
0.8 | 5.9 | [email protected] |
| 7.3 | 3.1 | HIGH |
|
1.3 | 5.9 | [email protected] |
| 9.3 | 2.0 | HIGH |
|
8.6 | 10.0 | [email protected] |
GHSA-fj7f-vq84-fh43 · 深刻度： medium · エコシステム： rubygems — Local Code Execution through Argument Injection via dash leading git url parameter in Gemfile.
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
— | CVE-2021-43809: 1 source package rows (ruby-bundler); 1 state rows across 1 repos (3.12-main); fixed 0, open 1. | https://security.alpinelinux.org/vuln/CVE-2021-43809 |
debian
|
not yet assigned | CVE-2021-43809 not yet assigned priority: Debian including 1 source packages (rubygems), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2021-43809 |
gentoo
|
normal | CVE-2021-43809: 1 GLSA(s) (202408-22), 1 atom(s) (dev-ruby/bundler); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-43809 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2021-43809 |
suse
|
high | CVE-2021-43809 severity important: SUSE including 268 source package names (2.19-54.2:ruby2.5-rubygem-bundler-1.16.1-150000.3.6.1, 2.5-29.2:ruby2.5-rubygem-bundler-1.16.1-150000.3.6.1, …), 338 product×package rows across 75 product lines (Container bci/ruby, Container suse/rmt-server, … (75 product lines)): Known Affected 231, Fixed 107. | https://www.suse.com/security/cve/CVE-2021-43809/ |
ubuntu
|
medium | CVE-2021-43809 medium priority: Ubuntu including 1 source packages (bundler), 15 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 9, ignored 2, needed 2, needs-triage 2. | https://ubuntu.com/security/CVE-2021-43809 |