CVE-2015-4176
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity,...
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity, which allows local users to read arbitrary files by leveraging user-namespace root access for deletion of a file or directory.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
5.5
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity, which allows local users to read arbitrary files by leveraging user-namespace root access for deletion of a file or directory.
- Record
CVE-2015-4176- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 2.1 Low
AV:L/AC:L/Au:N/C:N/I:P/A:N - Weakness
- CWE-200
- Updated
- 2026-11-02
CVE List No score
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity, which allows local users to read arbitrary files by leveraging user-namespace root access for deletion of a file or directory.
- Record
CVE-2015-4176- Updated
- 2026-11-02
EUVDEUVD-2015-4199 No score
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity, which allows local users to read arbitrary files by leveraging user-namespace root access for deletion of a file or directory.
- Record
EUVD-2015-4199- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-7254-j3fq-v7pj
5.5
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity,...
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity, which allows local users to read arbitrary files by leveraging user-namespace root access for deletion of a file or directory.
- Record
GHSA-7254-j3fq-v7pj- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-200
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2015-4176
5.5
fs/namespace.c in the Linux kernel before 4.0.2 does not properly support mount connectivity, which allows local users to read arbitrary files by leveraging user-namespace root access for deletion of a file or directory.
- Record
UBUNTU-CVE-2015-4176- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVMGASA-2015-0386 No score
Updated kernel packages provides 4.1 longterm and fixes security issues
This kernel update provides an upgrade to the upstream 4.1 longterm kernel series, currently based on 4.1.8 and resolves at least the following security issues:
It was found that the Linux kernel's keyring implementation would leak memory when adding a key to a keyring via the add_key() function. A local attacker could use this flaw to exhaust all available memory on the system. (CVE-2015-1333)
A flaw was found in the Linux kernel where the deletion of a file or directory could trigger an unmount and reveal data under a mount point. This flaw was inadvertently introduced with the new feature of being able to lazily unmount a mount tree when using file system user namespaces. (CVE-2015-4176)
A flaw was discovered in the kernel's collect_mounts function. If the kernel audit subsystem called collect_mounts to audit an unmounted path, it could panic the system. With this flaw, an unprivileged user could call umount (MNT_DETACH) to launch a denial-of-service attack. (CVE-2015-4177)
A flaw was found in the Linux kernel which is related to the user namespace lazily unmounting file systems. The fs_pin struct has two members (m_list and s_list) which are usually initialized on use in the pin_insert_group function. However, these members might go unmodified; in this case, the system panics when it attempts to destroy or free them. This flaw could be used to launch a denial-of-service attack. (CVE-2015-4178)
A DoS flaw was found for a Linux kernel built for the x86 architecture which had the KVM virtualization support(CONFIG_KVM) enabled. The kernel would be vulnerable to a NULL pointer dereference flaw in Linux kernel's kvm_apic_has_events() function while doing an ioctl. An unprivileged user able to access the "/dev/kvm" device could use this flaw to crash the system kernel. (CVE-2015-4692)
A flaw was found in the kernel's implementation of the Berkeley Packet Filter (BPF). A local attacker could craft BPF code to crash the system by creating a situation in which the JIT compiler would fail to correctly optimize the JIT image on the last pass. This would lead to the CPU executing instructions that were not part of the JIT code. (CVE-2015-4700)
The get_bitmap_file function in drivers/md/md.c in the Linux kernel before 4.1.6 does not initialize a certain bitmap data structure, which allows local users to obtain sensitive information from kernel memory via a GET_BITMAP_FILE ioctl call. (CVE-2015-5697)
Use-after-free vulnerability in the path_openat function in fs/namei.c in the Linux kernel 3.x and 4.x before 4.0.4 allows local users to cause a denial of service or possibly have unspecified other impact via O_TMPFILE filesystem operations that leverage a duplicate cleanup operation. (CVE-2015-5706)
It was discovered that an integer overflow error existed in the SCSIgeneric (sg) driver in the Linux kernel. A local attacker with writepermission to a SCSI generic device could use this to cause a denial of service (system crash) or potentially escalate their privileges. (CVE-2015-5707)
Additionally the following packages have been updated to add or improve support for the 4.1 series kernels: btrfs-progs, iproute2, xtables-addons, nvidia304, nvidia340, kernel-firmware-nonfree, radeon-firmware.
For other changes, see the referenced changelogs:
- Record
MGASA-2015-0386- Updated
- 2026-11-02
OSVMGASA-2015-0390 No score
Updated kernel-linus package provides 4.1 longterm and fixes security issues
This kernel-linus update provides an upgrade to the upstream 4.1 longterm kernel series, currently based on 4.1.8 and resolves at least the following security issues:
It was found that the Linux kernel's keyring implementation would leak memory when adding a key to a keyring via the add_key() function. A local attacker could use this flaw to exhaust all available memory on the system. (CVE-2015-1333)
A flaw was found in the Linux kernel where the deletion of a file or directory could trigger an unmount and reveal data under a mount point. This flaw was inadvertently introduced with the new feature of being able to lazily unmount a mount tree when using file system user namespaces. (CVE-2015-4176)
A flaw was discovered in the kernel's collect_mounts function. If the kernel audit subsystem called collect_mounts to audit an unmounted path, it could panic the system. With this flaw, an unprivileged user could call umount (MNT_DETACH) to launch a denial-of-service attack. (CVE-2015-4177)
A flaw was found in the Linux kernel which is related to the user namespace lazily unmounting file systems. The fs_pin struct has two members (m_list and s_list) which are usually initialized on use in the pin_insert_group function. However, these members might go unmodified; in this case, the system panics when it attempts to destroy or free them. This flaw could be used to launch a denial-of-service attack. (CVE-2015-4178)
A DoS flaw was found for a Linux kernel built for the x86 architecture which had the KVM virtualization support(CONFIG_KVM) enabled. The kernel would be vulnerable to a NULL pointer dereference flaw in Linux kernel's kvm_apic_has_events() function while doing an ioctl. An unprivileged user able to access the "/dev/kvm" device could use this flaw to crash the system kernel. (CVE-2015-4692)
A flaw was found in the kernel's implementation of the Berkeley Packet Filter (BPF). A local attacker could craft BPF code to crash the system by creating a situation in which the JIT compiler would fail to correctly optimize the JIT image on the last pass. This would lead to the CPU executing instructions that were not part of the JIT code. (CVE-2015-4700)
The get_bitmap_file function in drivers/md/md.c in the Linux kernel before 4.1.6 does not initialize a certain bitmap data structure, which allows local users to obtain sensitive information from kernel memory via a GET_BITMAP_FILE ioctl call. (CVE-2015-5697)
Use-after-free vulnerability in the path_openat function in fs/namei.c in the Linux kernel 3.x and 4.x before 4.0.4 allows local users to cause a denial of service or possibly have unspecified other impact via O_TMPFILE filesystem operations that leverage a duplicate cleanup operation. (CVE-2015-5706)
It was discovered that an integer overflow error existed in the SCSIgeneric (sg) driver in the Linux kernel. A local attacker with writepermission to a SCSI generic device could use this to cause a denial of service (system crash) or potentially escalate their privileges. (CVE-2015-5707)
For other changes, see the referenced changelogs:
- Record
MGASA-2015-0390- Updated
- 2026-11-02
OSVMGASA-2016-0015 No score
Updated kernel-tmb packages provides 4.1 longterm kernel and fixes security issues
This kernel-tmb update provides an upgrade to the upstream 4.1 longterm kernel series, currently based on 4.1.15 and resolves at least the following security issues:
It was found that the Linux kernel's keyring implementation would leak memory when adding a key to a keyring via the add_key() function. A local attacker could use this flaw to exhaust all available memory on the system. (CVE-2015-1333)
A flaw was found in the Linux kernel where the deletion of a file or directory could trigger an unmount and reveal data under a mount point. This flaw was inadvertently introduced with the new feature of being able to lazily unmount a mount tree when using file system user namespaces. (CVE-2015-4176)
A flaw was discovered in the kernel's collect_mounts function. If the kernel audit subsystem called collect_mounts to audit an unmounted path, it could panic the system. With this flaw, an unprivileged user could call umount (MNT_DETACH) to launch a denial-of-service attack. (CVE-2015-4177)
A flaw was found in the Linux kernel which is related to the user namespace lazily unmounting file systems. The fs_pin struct has two members (m_list and s_list) which are usually initialized on use in the pin_insert_group function. However, these members might go unmodified; in this case, the system panics when it attempts to destroy or free them. This flaw could be used to launch a denial-of-service attack. (CVE-2015-4178)
A DoS flaw was found for a Linux kernel built for the x86 architecture which had the KVM virtualization support(CONFIG_KVM) enabled. The kernel would be vulnerable to a NULL pointer dereference flaw in Linux kernel's kvm_apic_has_events() function while doing an ioctl. An unprivileged user able to access the "/dev/kvm" device could use this flaw to crash the system kernel. (CVE-2015-4692)
A flaw was found in the kernel's implementation of the Berkeley Packet Filter (BPF). A local attacker could craft BPF code to crash the system by creating a situation in which the JIT compiler would fail to correctly optimize the JIT image on the last pass. This would lead to the CPU executing instructions that were not part of the JIT code. (CVE-2015-4700)
The virtnet_probe function in drivers/net/virtio_net.c in the Linux kernel before 4.2 attempts to support a FRAGLIST feature without proper memory allocation, which allows guest OS users to cause a denial of service (buffer overflow and memory corruption) via a crafted sequence of fragmented packets. (CVE-2015-5156)
Moein Ghasemzadeh discovered that the USB WhiteHEAT serial driver contained hardcoded attributes about the USB devices. An attacker could construct a fake WhiteHEAT USB device that, when inserted, causes a denial of service (system crash) (CVE-2015-5257).
A guest to host DoS issue was found affecting various hypervisors. In that, a guest can DoS the host by triggering an infinite stream of "alignment check" (#AC) exceptions. This causes the microcode to enter an infinite loop where the core never receives another interrupt. The host kernel panics due to this effect (CVE-2015-5307).
The get_bitmap_file function in drivers/md/md.c in the Linux kernel before 4.1.6 does not initialize a certain bitmap data structure, which allows local users to obtain sensitive information from kernel memory via a GET_BITMAP_FILE ioctl call. (CVE-2015-5697)
Use-after-free vulnerability in the path_openat function in fs/namei.c in the Linux kernel 3.x and 4.x before 4.0.4 allows local users to cause a denial of service or possibly have unspecified other impact via O_TMPFILE filesystem operations that leverage a duplicate cleanup operation. (CVE-2015-5706)
It was discovered that an integer overflow error existed in the SCSIgeneric (sg) driver in the Linux kernel. A local attacker with writepermission to a SCSI generic device could use this to cause a denial of service (system crash) or potentially escalate their privileges. (CVE-2015-5707)
The __rds_conn_create function in…
- Record
MGASA-2016-0015- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
kernelMageia:5 From an advisory covering 10 CVEs |
before 4.1.8-1.mga5 | 4.1.8-1.mga5 |
kernel-userspace-headersMageia:5 From an advisory covering 10 CVEs |
before 4.1.8-1.mga5 | 4.1.8-1.mga5 |
kernel-firmwareMageia:5 From an advisory covering 10 CVEs |
before 20150722-1.mga5 | 20150722-1.mga5 |
btrfs-progsMageia:5 From an advisory covering 10 CVEs |
before 4.1.2-1.mga5 | 4.1.2-1.mga5 |
iproute2Mageia:5 From an advisory covering 10 CVEs |
before 4.1.1-1.mga5 | 4.1.1-1.mga5 |
xtables-addonsMageia:5 From an advisory covering 10 CVEs |
before 2.7-1.mga5 | 2.7-1.mga5 |
kmod-xtables-addonsMageia:5 From an advisory covering 10 CVEs |
before 2.7-4.mga5 | 2.7-4.mga5 |
kernel-firmware-nonfreeMageia:5 From an advisory covering 10 CVEs |
before 20150824-1.mga5.nonfree | 20150824-1.mga5.nonfree |
radeon-firmwareMageia:5 From an advisory covering 10 CVEs |
before 20150824-1.mga5.nonfree | 20150824-1.mga5.nonfree |
kmod-broadcom-wlMageia:5 From an advisory covering 10 CVEs |
before 6.30.223.248-36.mga5.nonfree | 6.30.223.248-36.mga5.nonfree |
Show 8 moreShow less
| Package | Affected | Fixed |
|---|---|---|
kmod-fglrxMageia:5 From an advisory covering 10 CVEs |
before 15.200.1046-5.mga5.nonfree | 15.200.1046-5.mga5.nonfree |
nvidia304Mageia:5 From an advisory covering 10 CVEs |
before 304.125-5.mga5.nonfree | 304.125-5.mga5.nonfree |
kmod-nvidia304Mageia:5 From an advisory covering 10 CVEs |
before 304.125-41.mga5.nonfree | 304.125-41.mga5.nonfree |
nvidia340Mageia:5 From an advisory covering 10 CVEs |
before 340.76-2.mga5.nonfree | 340.76-2.mga5.nonfree |
kmod-nvidia340Mageia:5 From an advisory covering 10 CVEs |
before 340.76-31.mga5.nonfree | 340.76-31.mga5.nonfree |
kmod-nvidia-currentMageia:5 From an advisory covering 10 CVEs |
before 346.82-3.mga5.nonfree | 346.82-3.mga5.nonfree |
kernel-linusMageia:5 From an advisory covering 9 CVEs |
before 4.1.8-1.mga5 | 4.1.8-1.mga5 |
kernel-tmbMageia:5 From an advisory covering 22 CVEs |
before 4.1.15-1.mga5 | 4.1.15-1.mga5 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2015-4176 is a medium vulnerability (CVSS 5.5) in Linux Kernel, published September 30, 2015. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.36%, the 29th percentile. No source names a fixed version.
References
openwall.com/lists/oss-security/2015/06/04/5
bugzilla.redhat.com/show_bug.cgi?id=1249442
github.com/torvalds/linux/commit/e0c9c0afd2fc958ffa34b697972721d81df8a56f
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.0.2
git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit?id=e0c9c0afd2fc958ffa34b697972721d81df8a56f
nvd.nist.gov/vuln/detail/CVE-2015-4176
Show 30 moreShow less
github.com/advisories/GHSA-7254-j3fq-v7pj
advisories.mageia.org/MGASA-2015-0386.html
bugs.mageia.org/show_bug.cgi?id=16655
kernelnewbies.org/Linux_4.0
kernelnewbies.org/Linux_4.1
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.1
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.2
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.3
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.4
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.5
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.6
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.7
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.8
advisories.mageia.org/MGASA-2015-0390.html
bugs.mageia.org/show_bug.cgi?id=16654
advisories.mageia.org/MGASA-2016-0015.html
bugs.mageia.org/show_bug.cgi?id=17401
bugs.mageia.org/show_bug.cgi?id=16915
bugs.mageia.org/show_bug.cgi?id=17010
bugs.mageia.org/show_bug.cgi?id=17034
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.9
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.10
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.11
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.12
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.13
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.14
kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.15
ubuntu.com/security/CVE-2015-4176
openwall.com/lists/oss-security/2015/06/04/9
cve.org/CVERecord?id=CVE-2015-4176
Left out here: the rest of 1 source description. The JSON record has them.