NVD Vulnerability Detail

CVE-2014-7975

Summary	The do_umount function in fs/namespace.c in the Linux kernel through 3.17 does not require the CAP_SYS_ADMIN capability for do_remount_sb calls that change the root filesystem to read-only, which allows local users to cause a denial of service (loss of writability) by making certain unshare system calls, clearing the / MNT_LOCKED flag, and making an MNT_FORCE umount system call.
Publication Date	Oct. 13, 2014, 7:55 p.m.
Registration Date	Jan. 26, 2021, 3:19 p.m.
Last Update	Nov. 21, 2024, 11:18 a.m.

CVSS3.1 : MEDIUM
スコア	5.5
Vector	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
攻撃元区分(AV)	ローカル
攻撃条件の複雑さ(AC)	低
攻撃に必要な特権レベル(PR)	低
利用者の関与(UI)	不要
影響の想定範囲(S)	変更なし
機密性への影響(C)	なし
完全性への影響(I)	なし
可用性への影響(A)	高

CVSS2.0 : MEDIUM
Score	4.9
Vector	AV:L/AC:L/Au:N/C:N/I:N/A:C
攻撃元区分(AV)	ローカル
攻撃条件の複雑さ(AC)	低
攻撃前の認証要否(Au)	不要
機密性への影響(C)	なし
完全性への影響(I)	なし
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:o:linux:linux_kernel::::::::			3.17

Configuration2	or higher	or less	more than	less than
cpe:2.3:o:canonical:ubuntu_linux:14.10:::::::*
cpe:2.3:o:canonical:ubuntu_linux:12.04::::esm:::
cpe:2.3:o:canonical:ubuntu_linux:14.04::::esm:::
cpe:2.3:o:canonical:ubuntu_linux:10.04::::-:::

Related information, measures and tools

No	URL	タグ
1	http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0ef3a56b1c466629cd0bf482b09c7b0e5a085bb5	Mailing List Patch Vendor Advisory
2	http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0ef3a56b1c466629cd0bf482b09c7b0e5a085bb5	Mailing List Patch Vendor Advisory
3	http://secunia.com/advisories/60174	Broken Link
4	http://secunia.com/advisories/60174	Broken Link
5	http://secunia.com/advisories/61145	Broken Link
6	http://secunia.com/advisories/61145	Broken Link
7	http://secunia.com/advisories/62633	Broken Link
8	http://secunia.com/advisories/62633	Broken Link
9	http://secunia.com/advisories/62634	Broken Link
10	http://secunia.com/advisories/62634	Broken Link
11	http://thread.gmane.org/gmane.linux.kernel.stable/109312	Broken Link
12	http://thread.gmane.org/gmane.linux.kernel.stable/109312	Broken Link
13	http://www.openwall.com/lists/oss-security/2014/10/08/22	Mailing List Third Party Advisory
14	http://www.openwall.com/lists/oss-security/2014/10/08/22	Mailing List Third Party Advisory
15	http://www.securityfocus.com/bid/70314	Third Party Advisory VDB Entry
16	http://www.securityfocus.com/bid/70314	Third Party Advisory VDB Entry
17	http://www.securitytracker.com/id/1031180	Third Party Advisory VDB Entry
18	http://www.securitytracker.com/id/1031180	Third Party Advisory VDB Entry
19	http://www.ubuntu.com/usn/USN-2415-1	Third Party Advisory
20	http://www.ubuntu.com/usn/USN-2415-1	Third Party Advisory
21	http://www.ubuntu.com/usn/USN-2416-1	Third Party Advisory
22	http://www.ubuntu.com/usn/USN-2416-1	Third Party Advisory
23	http://www.ubuntu.com/usn/USN-2417-1	Third Party Advisory
24	http://www.ubuntu.com/usn/USN-2417-1	Third Party Advisory
25	http://www.ubuntu.com/usn/USN-2418-1	Third Party Advisory
26	http://www.ubuntu.com/usn/USN-2418-1	Third Party Advisory
27	http://www.ubuntu.com/usn/USN-2419-1	Third Party Advisory
28	http://www.ubuntu.com/usn/USN-2419-1	Third Party Advisory
29	http://www.ubuntu.com/usn/USN-2420-1	Third Party Advisory
30	http://www.ubuntu.com/usn/USN-2420-1	Third Party Advisory
31	http://www.ubuntu.com/usn/USN-2421-1	Third Party Advisory
32	http://www.ubuntu.com/usn/USN-2421-1	Third Party Advisory
33	https://access.redhat.com/errata/RHSA-2017:1842	Third Party Advisory
34	https://access.redhat.com/errata/RHSA-2017:1842	Third Party Advisory
35	https://access.redhat.com/errata/RHSA-2017:2077	Third Party Advisory
36	https://access.redhat.com/errata/RHSA-2017:2077	Third Party Advisory
37	https://bugzilla.redhat.com/show_bug.cgi?id=1151108	Issue Tracking Patch Third Party Advisory
38	https://bugzilla.redhat.com/show_bug.cgi?id=1151108	Issue Tracking Patch Third Party Advisory
39	https://exchange.xforce.ibmcloud.com/vulnerabilities/96994	Third Party Advisory VDB Entry
40	https://exchange.xforce.ibmcloud.com/vulnerabilities/96994	Third Party Advisory VDB Entry

Common Vulnerabilities List

JVN Vulnerability Information

Linux Kernel の fs/namespace.c 内の do_umount 関数におけるサービス運用妨害 (DoS) の脆弱性

Title	Linux Kernel の fs/namespace.c 内の do_umount 関数におけるサービス運用妨害 (DoS) の脆弱性
Summary	Linux Kernel の fs/namespace.c 内の do_umount 関数は、読み取り専用のルートファイルシステムを変更する do_remount_sb の呼び出しに対する CAP_SYS_ADMIN ケーパビリティを要求しないため、サービス運用妨害 (書き込み権限の損失) 状態にされる脆弱性が存在します。
Possible impacts	ローカルユーザにより、特定の共有されないシステムコールの作成、/ MNT_LOCKED のフラグの消去、および MNT_FORCE のアンマウントシステムコールの作成をされることで、サービス運用妨害 (書き込み権限の損失) 状態にされる可能性があります。
Solution	ベンダより正式な対策が公開されています。ベンダ情報を参照して適切な対策を実施してください。
Publication Date	Oct. 9, 2014, midnight
Registration Date	Oct. 20, 2014, 6:13 p.m.
Last Update	Nov. 12, 2014, 6:04 p.m.

Affected System

Linux

Linux Kernel 3.17 まで

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-2014-7975	http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2014-7975
National Vulnerability Database (NVD)
2	CVE-2014-7975	http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-7975

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

ベンダー情報

No	Name	URL
Linux Kernel
1	Linux Kernel Archives	http://www.kernel.org
Linux kernel source tree
2	Merge branch 'CVE-2014-7975' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux	http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0ef3a56b1c466629cd0bf482b09c7b0e5a085bb5
Red Hat Bugzilla
3	Bug 1151108	https://bugzilla.redhat.com/show_bug.cgi?id=1151108

Change Log

No	Changed Details	Date of change
0	[2014年10月20日] 掲載 [2014年11月12日] ベンダ情報：kernel.org (Merge branch 'CVE-2014-7975' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux) を追加	Feb. 17, 2018, 10:37 a.m.