GHSA-w853-v86g-gv7j · 深刻度： high — Issue summary: A signed integer overflow when sizing the destination buffer for Unicode output in...
Issue summary: A signed integer overflow when sizing the destination buffer for Unicode output in ASN1_mbstring_ncopy() can lead to a heap buffer overflow. Impact summary: A heap buffer overflow may lead to a crash or possibly attacker controlled code execution or other undefined behaviour. In ASN1_mbstring_copy() and ASN1_mbstring_ncopy() the destination size for Unicode output is computed in a signed int: by left shift of the input character count for BMPSTRING (UTF-16) and UNIVERSALSTRING (UTF-32), and by summing per-character byte counts for UTF8STRING. The calculation overflows when the input reaches around 2^30 characters. In the worst case (UNIVERSALSTRING at 2^30 characters) the size wraps to zero, OPENSSL_malloc(1) is called, and the subsequent character copy writes several gigabytes past the one-byte allocation. X.509 certificate processing routes through ASN1_STRING_set_by_NID(), whose DIRSTRING_TYPE mask excludes UNIVERSALSTRING and whose per-NID size limits cap the input length; no network protocol or certificate-handling path in OpenSSL exercises the overflow. Triggering the bug requires an application that calls ASN1_mbstring_copy() or ASN1_mbstring_ncopy() directly, or registers a custom string type via ASN1_STRING_TABLE_add(), with attacker-controlled input on the order of half a gigabyte or more. For these reasons this issue was assigned Low severity. The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.
総合評価: CVE-2026-7383 は中リスク（42.1/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 0.36%、28 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 | 2026-06-18 | 0.32% | 0.36% | +0.03% |
| 2 | 2026-06-15 | 0.07% | 0.32% | +0.26% |
| 3 | 2026-06-10 | — | 0.07% | — |
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 |
|---|---|---|---|---|---|---|
| 8.1 | 3.1 | HIGH |
|
2.2 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
GHSA-w853-v86g-gv7j · 深刻度： high — Issue summary: A signed integer overflow when sizing the destination buffer for Unicode output in...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-7383 not yet assigned priority: Debian including 1 source packages (openssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2026-7383 |
redhat
|
low | — | https://access.redhat.com/security/cve/CVE-2026-7383 |
suse
|
medium | CVE-2026-7383 severity moderate: SUSE including 70 source package names (latest:libexpat1-2.7.1-4.1, latest:libopenssl3-3.1.4-slfo.1.1_10.1, …), 364 product×package rows across 68 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (68 product lines)): First Fixed 240, Fixed 69, Known Not Affected 55. | https://www.suse.com/security/cve/CVE-2026-7383/ |
ubuntu
|
low | CVE-2026-7383 low priority: Ubuntu including 5 source packages (edk2, nodejs, openssl, openssl-fips, openssl1.0), 35 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): needs-triage 12, released 9, DNE 8, not-affected 5, needed 1. | https://ubuntu.com/security/CVE-2026-7383 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| openssl | openssl | >= 1.0.2, < 1.0.2zq | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 1.1.1, < 1.1.1zh | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.0.0, < 3.0.21 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.4.0, < 3.4.6 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.5.0, < 3.5.7 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | >= 3.6.0, < 3.6.3 | cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* |
| openssl | openssl | 4.0.0 | cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:* |