A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12.
総合評価: CVE-2021-3695 は低リスク（30.6/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.44%、35 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 | 0.06% | 0.44% | +0.38% |
| 2 | 2025-03-17 | 0.05% | 0.06% | +0.01% |
| 3 | 2023-03-07 | — | 0.05% | — |
EPSS の全履歴 （全 6 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 |
|---|---|---|---|---|---|---|
| 4.5 | 3.1 | MEDIUM |
|
1.0 | 3.4 | [email protected] |
| 4.4 | 2.0 | MEDIUM |
|
3.4 | 6.4 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2021-3695 not yet assigned priority: Debian including 1 source packages (grub2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2021-3695 |
gentoo
|
high | CVE-2021-3695: 1 GLSA(s) (202209-12), 1 atom(s) (sys-boot/grub); latest impact high. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-3695 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2021-3695 |
suse
|
high | — | https://www.suse.com/security/cve/CVE-2021-3695/ |
ubuntu
|
medium | CVE-2021-3695 medium priority: Ubuntu including 3 source packages (grub2, grub2-signed, grub2-unsigned), 40 status rows across 14 suites (bionic, focal, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 24, released 6, ignored 3, needed 3, needs-triage 3, DNE 1. | https://ubuntu.com/security/CVE-2021-3695 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| gnu | grub2 | >= 2.00, < 2.12 | cpe:2.3:a:gnu:grub2:*:*:*:*:*:*:*:* |
| fedoraproject | fedora | 36 | cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:* |
| redhat | developer_tools | 1.0 | cpe:2.3:a:redhat:developer_tools:1.0:*:*:*:*:*:*:* |
| redhat | openshift | 3.0 | cpe:2.3:a:redhat:openshift:3.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux | 8.0 | cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux | 8.1 | cpe:2.3:o:redhat:enterprise_linux:8.1:*:*:*:*:*:*:* |
| redhat | enterprise_linux | 8.4 | cpe:2.3:o:redhat:enterprise_linux:8.4:*:*:*:*:*:*:* |
| redhat | enterprise_linux | 9.0 | cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_eus | 8.2 | cpe:2.3:o:redhat:enterprise_linux_eus:8.2:*:*:*:*:*:*:* |
| redhat | enterprise_linux_eus | 8.4 | cpe:2.3:o:redhat:enterprise_linux_eus:8.4:*:*:*:*:*:*:* |
| redhat | enterprise_linux_eus | 8.6 | cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_eus | 9.0 | cpe:2.3:o:redhat:enterprise_linux_eus:9.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_for_power_little_endian | 8.0 | cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_for_power_little_endian | 9.0 | cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:9.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_for_power_little_endian_eus | 8.2 | cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.2:*:*:*:*:*:*:* |
| redhat | enterprise_linux_for_power_little_endian_eus | 8.4 | cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.4:*:*:*:*:*:*:* |
| redhat | enterprise_linux_for_power_little_endian_eus | 8.6 | cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:8.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_for_power_little_endian_eus | 9.0 | cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:9.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_aus | 8.2 | cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_aus | 8.4 | cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_aus | 8.6 | cpe:2.3:o:redhat:enterprise_linux_server_aus:8.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions | 8.1 | cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.1:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions | 8.2 | cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.2:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions | 8.4 | cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.4:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions | 8.6 | cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:8.6:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions | 9.0 | cpe:2.3:o:redhat:enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions:9.0:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_tus | 8.2 | cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_tus | 8.4 | cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:* |
| redhat | enterprise_linux_server_tus | 8.6 | cpe:2.3:o:redhat:enterprise_linux_server_tus:8.6:*:*:*:*:*:*:* |
| redhat | openshift_container_platform | 4.6 | cpe:2.3:a:redhat:openshift_container_platform:4.6:*:*:*:*:*:*:* |
| redhat | openshift_container_platform | 4.9 | cpe:2.3:a:redhat:openshift_container_platform:4.9:*:*:*:*:*:*:* |
| redhat | openshift_container_platform | 4.10 | cpe:2.3:a:redhat:openshift_container_platform:4.10:*:*:*:*:*:*:* |
| redhat | codeready_linux_builder | — | cpe:2.3:a:redhat:codeready_linux_builder:-:*:*:*:*:*:*:* |
| netapp | ontap_select_deploy_administration_utility | — | cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:* |
| URL | タグ |
|---|---|
| https://bugzilla.redhat.com/show_bug.cgi?id=1991685 | Issue Tracking Third Party Advisory |
| https://security.gentoo.org/glsa/202209-12 | Third Party Advisory |
| https://security.netapp.com/advisory/ntap-20220930-0001/ | Third Party Advisory |