GHSA-8vqr-qjwx-82mw · 深刻度： high · エコシステム： rubygems — Rack's multipart parsing without Content-Length header allows unbounded chunked file uploads
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser only wraps the request body in a BoundedIO when CONTENT_LENGTH is present. When a multipart/form-data request is sent without a Content-Length header, such as with HTTP chunked transfer encoding, multipart parsing continues until end-of-stream with no total size limit. For file parts, the uploaded body is written directly to a temporary file on disk rather than being constrained by the buffered in-memory upload limit. An unauthenticated attacker can therefore stream an arbitrarily large multipart file upload and consume unbounded disk space. This results in a denial of service condition for Rack applications that accept multipart form data. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.
総合評価: CVE-2026-34829 は低リスク（37.1/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 0.28%、20 パーセンタイル） 推奨対応: 悪用情報と EPSS の推移を監視し、必要に応じて優先度を見直してください。
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。
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 | 0.05% | 0.28% | +0.23% |
| 2 | 2026-04-08 | 0.04% | 0.05% | +0.01% |
| 3 | 2026-04-03 | — | 0.04% | — |
EPSS の全履歴 （全 3 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 |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
GHSA-8vqr-qjwx-82mw · 深刻度： high · エコシステム： rubygems — Rack's multipart parsing without Content-Length header allows unbounded chunked file uploads
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-34829 not yet assigned priority: Debian including 1 source packages (ruby-rack), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. | https://security-tracker.debian.org/tracker/CVE-2026-34829 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2026-34829 |
suse
|
high | CVE-2026-34829 severity important: SUSE including 2 source package names (hawk2, ruby4.0-rubygem-rack-2.2-2.2.23-1.1), 7 product×package rows across 7 product lines (SUSE Linux Enterprise High Availability Extension 12 SP5, SUSE Linux Enterprise High Availability Extension 15 SP4, … (7 product lines)): Known Not Affected 6, Fixed 1. | https://www.suse.com/security/cve/CVE-2026-34829/ |
ubuntu
|
medium | CVE-2026-34829 medium priority: Ubuntu including 1 source packages (ruby-rack), 9 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): released 4, ignored 3, needed 1, not-affected 1. | https://ubuntu.com/security/CVE-2026-34829 |
| URL | タグ |
|---|---|
| https://github.com/rack/rack/security/advisories/GHSA-8vqr-qjwx-82mw | Vendor Advisory |