GHSA-38jv-5279-wg99 · 深刻度： high · エコシステム： pip — Decompression-bomb safeguards bypassed when following HTTP redirects (streaming API)
urllib3 is an HTTP client library for Python. urllib3's streaming API is designed for the efficient handling of large HTTP responses by reading the content in chunks, rather than loading the entire response body into memory at once. urllib3 can perform decoding or decompression based on the HTTP `Content-Encoding` header (e.g., `gzip`, `deflate`, `br`, or `zstd`). When using the streaming API, the library decompresses only the necessary bytes, enabling partial content consumption. Starting in version 1.22 and prior to version 2.6.3, for HTTP redirect responses, the library would read the entire response body to drain the connection and decompress the content unnecessarily. This decompression occurred even before any read methods were called, and configured read limits did not restrict the amount of decompressed data. As a result, there was no safeguard against decompression bombs. A malicious server could exploit this to trigger excessive resource consumption on the client. Applications and libraries are affected when they stream content from untrusted sources by setting `preload_content=False` when they do not disable redirects. Users should upgrade to at least urllib3 v2.6.3, in which the library does not decode content of redirect responses when `preload_content=False`. If upgrading is not immediately possible, disable redirects by setting `redirect=False` for requests to untrusted source.
総合評価: CVE-2026-21441 は高リスク（66.9/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 2.67%、84 パーセンタイル） 根拠: 直近 1 日で EPSS が +1.99% 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: 悪用可能性が高いため、影響範囲の確認と修補の優先付けを推奨します。
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 | 2026-06-30 | 0.68% | 2.67% | +1.99% |
| 2 | 2026-06-23 | 0.52% | 0.68% | +0.16% |
| 3 | 2026-06-15 | — | 0.52% | — |
EPSS の全履歴 （全 4 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 |
|---|---|---|---|---|---|---|
| 8.9 | 4.0 | HIGH |
|
— | — | [email protected] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c |
GHSA-38jv-5279-wg99 · 深刻度： high · エコシステム： pip — Decompression-bomb safeguards bypassed when following HTTP redirects (streaming API)
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
— | CVE-2026-21441: 1 source package rows (py3-urllib3); 32 state rows across 6 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, 3.23-main, edge-main); fixed 5, open 27. | https://security.alpinelinux.org/vuln/CVE-2026-21441 |
debian
|
not yet assigned | CVE-2026-21441 not yet assigned priority: Debian including 1 source packages (python-urllib3), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2026-21441 |
redhat
|
high | — | https://access.redhat.com/security/cve/CVE-2026-21441 |
suse
|
medium | CVE-2026-21441 severity moderate: SUSE including 382 source package names (2.1.3-6.24:NetworkManager-1.42.6-6.1, 2.1.3-6.24:NetworkManager-wwan-1.42.6-6.1, …), 636 product×package rows across 202 product lines (Container suse/manager/4.3/proxy-tftpd, Container suse/manager/5.0/x86_64/proxy-tftpd, … (202 product lines)): Fixed 402, Known Affected 231, First Fixed 3. | https://www.suse.com/security/cve/CVE-2026-21441/ |
ubuntu
|
medium | CVE-2026-21441 medium priority: Ubuntu including 2 source packages (python-pip, python-urllib3), 18 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): released 6, not-affected 4, ignored 3, needed 3, needs-triage 2. | https://ubuntu.com/security/CVE-2026-21441 |