c-ares is an asynchronous resolver library. When /dev/urandom or RtlGenRandom() are unavailable, c-ares uses rand() to generate random numbers used for DNS query ids. This is not a CSPRNG, and it is also not seeded by srand() so will generate predictable output. Input from the random number generator is fed into a non-compilant RC4 implementation and may not be as strong as the original RC4 implementation. No attempt is made to look for modern OS-provided CSPRNGs like arc4random() that is widely available. This issue has been fixed in version 1.19.1.
総合評価: CVE-2023-31147 は中リスク（43.7/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.91%、55 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 | 0.09% | 0.91% | +0.82% |
| 2 | 2025-11-21 | 0.33% | 0.09% | -0.24% |
| 3 | 2025-11-18 | — | 0.33% | — |
EPSS の全履歴 （全 10 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 |
|---|---|---|---|---|---|---|
| 5.9 | 3.1 | MEDIUM |
|
2.2 | 3.6 | [email protected] |
| 6.5 | 3.1 | MEDIUM |
|
3.9 | 2.5 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
medium | CVE-2023-31147: 1 source package rows (c-ares); 5 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 0, open 5. | https://security.alpinelinux.org/vuln/CVE-2023-31147 |
debian
|
unimportant | CVE-2023-31147 unimportant priority: Debian including 1 source packages (c-ares), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. | https://security-tracker.debian.org/tracker/CVE-2023-31147 |
gentoo
|
normal | CVE-2023-31147: 1 GLSA(s) (202310-09), 1 atom(s) (net-dns/c-ares); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2023-31147 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2023-31147 |
suse
|
medium | CVE-2023-31147 severity moderate: SUSE including 305 source package names (0.3.2-1.2:libcares2-1.19.1-150000.3.23.1, 0.3.32-3.4:libcares2-1.19.1-150000.3.23.1, …), 690 product×package rows across 317 product lines (Container bci/nodejs, Container caasp/v4/cilium, … (317 product lines)): Fixed 538, Known Affected 152. | https://www.suse.com/security/cve/CVE-2023-31147/ |
ubuntu
|
negligible | CVE-2023-31147 negligible priority: Ubuntu including 1 source packages (c-ares), 8 status rows across 8 suites (bionic, focal, jammy, kinetic, lunar, trusty, upstream, xenial): not-affected 6, ignored 1, released 1. | https://ubuntu.com/security/CVE-2023-31147 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| c-ares_project | c-ares | < 1.19.1 | cpe:2.3:a:c-ares_project:c-ares:*:*:*:*:*:*:*:* |
| fedoraproject | fedora | 37 | cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:* |
| fedoraproject | fedora | 38 | cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:* |
| URL | タグ |
|---|---|
| https://github.com/c-ares/c-ares/releases/tag/cares-1_19_1 | Release Notes |
| https://github.com/c-ares/c-ares/security/advisories/GHSA-8r8p-23f3-64c2 | Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/[email protected]/message/B5Z5XFNXTNPTCBBVXFDNZQVLLIE6VRBY/ | Mailing List Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/[email protected]/message/UBFWILTA33LOSV23P44FGTQQIDRJHIY7/ | Mailing List Third Party Advisory |
| https://security.gentoo.org/glsa/202310-09 | Third Party Advisory |