NVD Vulnerability Detail

CVE-2015-8370

Summary	Multiple integer underflows in Grub2 1.98 through 2.02 allow physically proximate attackers to bypass authentication, obtain sensitive information, or cause a denial of service (disk corruption) via backspace characters in the (1) grub_username_get function in grub-core/normal/auth.c or the (2) grub_password_get function in lib/crypto.c, which trigger an "Off-by-two" or "Out of bounds overwrite" memory error.
Publication Date	Dec. 17, 2015, 6:59 a.m.
Registration Date	Jan. 26, 2021, 2:58 p.m.
Last Update	Nov. 21, 2024, 11:38 a.m.

CVSS2.0 : MEDIUM
Score	6.9
Vector	AV:L/AC:M/Au:N/C:C/I:C/A:C
攻撃元区分(AV)	ローカル
攻撃条件の複雑さ(AC)	中
攻撃前の認証要否(Au)	不要
機密性への影響(C)	高
完全性への影響(I)	高
可用性への影響(A)	高
Get all privileges.	いいえ
Get user privileges	いいえ
Get other privileges	いいえ
User operation required	いいえ

Affected software configurations

Configuration1	or higher	or less	more than	less than
cpe:2.3:a:gnu:grub2:2.02:::::::*
cpe:2.3:a:gnu:grub2:2.01:::::::*
cpe:2.3:a:gnu:grub2:2.00:::::::*
cpe:2.3:a:gnu:grub2:1.99:::::::*
cpe:2.3:a:gnu:grub2:1.98:::::::*

Configuration2		or higher	or less	more than	less than
cpe:2.3:o:fedoraproject:fedora:23:::::::*

Related information, measures and tools

No	URL	タグ
1	http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html	Exploit
2	http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html	Exploit
3	http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.html
4	http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.html
5	http://lists.fedoraproject.org/pipermail/package-announce/2015-December/174049.html
6	http://lists.fedoraproject.org/pipermail/package-announce/2015-December/174049.html
7	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00037.html
8	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00037.html
9	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00039.html
10	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00039.html
11	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00040.html
12	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00040.html
13	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00041.html
14	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00041.html
15	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00043.html
16	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00043.html
17	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00044.html
18	http://lists.opensuse.org/opensuse-security-announce/2015-12/msg00044.html
19	http://lists.opensuse.org/opensuse-security-announce/2016-01/msg00003.html
20	http://lists.opensuse.org/opensuse-security-announce/2016-01/msg00003.html
21	http://packetstormsecurity.com/files/134831/Grub2-Authentication-Bypass.html
22	http://packetstormsecurity.com/files/134831/Grub2-Authentication-Bypass.html
23	http://rhn.redhat.com/errata/RHSA-2015-2623.html
24	http://rhn.redhat.com/errata/RHSA-2015-2623.html
25	http://seclists.org/fulldisclosure/2015/Dec/69
26	http://seclists.org/fulldisclosure/2015/Dec/69
27	http://www.debian.org/security/2015/dsa-3421
28	http://www.debian.org/security/2015/dsa-3421
29	http://www.openwall.com/lists/oss-security/2015/12/15/6
30	http://www.openwall.com/lists/oss-security/2015/12/15/6
31	http://www.openwall.com/lists/oss-security/2024/01/15/3
32	http://www.openwall.com/lists/oss-security/2024/01/15/3
33	http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html	Patch
34	http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html	Patch
35	http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
36	http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
37	http://www.securityfocus.com/archive/1/537115/100/0/threaded
38	http://www.securityfocus.com/archive/1/537115/100/0/threaded
39	http://www.securityfocus.com/bid/79358
40	http://www.securityfocus.com/bid/79358
41	http://www.securitytracker.com/id/1034422
42	http://www.securitytracker.com/id/1034422
43	http://www.ubuntu.com/usn/USN-2836-1
44	http://www.ubuntu.com/usn/USN-2836-1
45	https://security.gentoo.org/glsa/201512-03
46	https://security.gentoo.org/glsa/201512-03

Common Vulnerabilities List

No	CWE	Name	URL
1	CWE-264	認可・権限・アクセス制御	https://cwe.mitre.org/data/definitions/264.html

JVN Vulnerability Information

Grub2 における整数アンダーフローの脆弱性

Title	Grub2 における整数アンダーフローの脆弱性
Summary	Grub2 には、整数アンダーフローの脆弱性が存在します。
Possible impacts	物理的に端末の操作が可能な攻撃者により、(1) grub-core/normal/auth.c の grub_username_get 関数、または (2) lib/crypto.c の grub_password_get 関数のバックスペース文字を介して、"二つずれ (Off-by-two)"、または "Out of bounds overwrite" メモリエラーを誘発されることで、認証を回避され、重要な情報を取得される、またはサービス運用妨害 (ディスク破損) 状態にされる可能性があります。
Solution	ベンダ情報および参考情報を参照して適切な対策を実施してください。
Publication Date	Dec. 14, 2015, midnight
Registration Date	Dec. 18, 2015, 4:46 p.m.
Last Update	Jan. 28, 2016, 5:42 p.m.

Affected System

オラクル

Oracle Solaris 11

GNU Project

GRUB 2 1.98 から 2.02

Fedora Project

Fedora 23

CVE (情報セキュリティ共通脆弱性識別子)

No	Name	URL
Common Vulnerabilities and Exposures (CVE)
1	CVE-2015-8370	http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8370
2	CVE-2015-8370	http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8370
National Vulnerability Database (NVD)
3	CVE-2015-8370	http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-8370
4	CVE-2015-8370	http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-8370

CWE (共通脆弱性タイプ一覧)

No	Name	URL
JVNDB
1	CWE-264	https://jvndb.jvn.jp/ja/cwe/CWE-264.html
2	CWE-264	https://jvndb.jvn.jp/ja/cwe/CWE-264.html

ベンダー情報

No	Name	URL
Fedora Update Notification
1	FEDORA-2015-cebe5133e7	http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.html
2	FEDORA-2015-cebe5133e7	http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173703.html
GitHub
3	GRUB 2	http://www.gnu.org/software/grub/
4	GRUB 2	http://www.gnu.org/software/grub/
Oracle Critical Patch Update
5	Oracle Critical Patch Update Advisory - January 2016	http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html
6	Oracle Critical Patch Update Advisory - January 2016	http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html
7	Text Form of Oracle Critical Patch Update - January 2016 Risk Matrices	http://www.oracle.com/technetwork/topics/security/cpujan2016verbose-2367956.html
8	Text Form of Oracle Critical Patch Update - January 2016 Risk Matrices	http://www.oracle.com/technetwork/topics/security/cpujan2016verbose-2367956.html
SECURITY BLOG
9	January 2016 Critical Patch Update Released	https://blogs.oracle.com/security/entry/january_2016_critical_patch_update
10	January 2016 Critical Patch Update Released	https://blogs.oracle.com/security/entry/january_2016_critical_patch_update

その他

No	Name	URL
関連文書
1	Back to 28: Grub2 Authentication 0-Day	http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html
2	Back to 28: Grub2 Authentication 0-Day	http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html

Change Log

No	Changed Details	Date of change
0	[2015年12月18日] 掲載 [2016年01月28日] 影響を受けるシステム：ベンダ情報の追加に伴い内容を更新ベンダ情報：オラクル (Oracle Critical Patch Update Advisory - January 2016) を追加ベンダ情報：オラクル (Text Form of Oracle Critical Patch Update - January 2016 Risk Matrices) を追加ベンダ情報：オラクル (January 2016 Critical Patch Update Released) を追加	Feb. 17, 2018, 10:37 a.m.
0	[2015年12月18日] 掲載 [2016年01月28日] 影響を受けるシステム：ベンダ情報の追加に伴い内容を更新ベンダ情報：オラクル (Oracle Critical Patch Update Advisory - January 2016) を追加ベンダ情報：オラクル (Text Form of Oracle Critical Patch Update - January 2016 Risk Matrices) を追加ベンダ情報：オラクル (January 2016 Critical Patch Update Released) を追加	Feb. 17, 2018, 10:37 a.m.