GHSA-84j7-475p-hp8v · 深刻度： medium · エコシステム： rubygems — HTTP Response Splitting in Puma
In Puma (RubyGem) before 4.3.2 and before 3.12.3, if an application using Puma allows untrusted input in a response header, an attacker can use newline characters (i.e. `CR`, `LF` or`/r`, `/n`) to end the header and inject malicious content, such as additional headers or an entirely new response body. This vulnerability is known as HTTP Response Splitting. While not an attack in itself, response splitting is a vector for several other attacks, such as cross-site scripting (XSS). This is related to CVE-2019-16254, which fixed this vulnerability for the WEBrick Ruby web server. This has been fixed in versions 4.3.2 and 3.12.3 by checking all headers for line endings and rejecting headers with those characters.
総合評価: CVE-2020-5247 は中リスク（55.3/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 2.49%、82 パーセンタイル） 推奨対応: 影響資産を整理し、修補計画に組み込んでください。
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 | 2.09% | 2.49% | +0.39% |
| 2 | 2026-03-04 | 3.07% | 2.09% | -0.97% |
| 3 | 2026-03-01 | — | 3.07% | — |
EPSS の全履歴 （全 50 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 |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
2.3 | 3.7 | [email protected] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
GHSA-84j7-475p-hp8v · 深刻度： medium · エコシステム： rubygems — HTTP Response Splitting in Puma
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
high | CVE-2020-5247: 1 source package rows (ruby); 20 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 0, open 20. | https://security.alpinelinux.org/vuln/CVE-2020-5247 |
debian
|
not yet assigned | CVE-2020-5247 not yet assigned priority: Debian including 1 source packages (puma), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2020-5247 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2020-5247 |
suse
|
medium | CVE-2020-5247 severity moderate: SUSE including 294 source package names (ansible-2.2.3.0-12.2, ardana-ansible-8.0+git.1583432621.24fa60e-3.70.1, …), 500 product×package rows across 24 product lines (HPE Helion OpenStack 8, SUSE Linux Enterprise High Performance Computing 15-ESPOS, … (24 product lines)): Fixed 500. | https://www.suse.com/security/cve/CVE-2020-5247/ |
ubuntu
|
medium | CVE-2020-5247 medium priority: Ubuntu including 1 source packages (puma), 6 status rows across 6 suites (bionic, eoan, focal, trusty, upstream, xenial): DNE 3, ignored 1, needs-triage 1, not-affected 1. | https://ubuntu.com/security/CVE-2020-5247 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| puma | puma | <= 3.12.3 | cpe:2.3:a:puma:puma:*:*:*:*:*:ruby:*:* |
| puma | puma | >= 4.0.0, <= 4.3.2 | cpe:2.3:a:puma:puma:*:*:*:*:*:ruby:*:* |
| ruby-lang | ruby | <= 2.3.0 | cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:* |
| ruby-lang | ruby | >= 2.4.0, <= 2.4.7 | cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:* |
| ruby-lang | ruby | >= 2.5.0, <= 2.5.6 | cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:* |
| ruby-lang | ruby | >= 2.6.0, <= 2.6.4 | cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:* |
| ruby-lang | ruby | 2.7.0 | cpe:2.3:a:ruby-lang:ruby:2.7.0:preview1:*:*:*:*:*:* |
| debian | debian_linux | 9.0 | cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* |
| fedoraproject | fedora | 30 | cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:* |
| fedoraproject | fedora | 31 | cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* |
| fedoraproject | fedora | 32 | cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* |