CVE-2016-4557

Linux Kernel 4.4 (Ubuntu 16.04) - 'BPF' Local Privilege Escalation

Severity Score

7.8

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

The replace_map_fd_with_map_ptr function in kernel/bpf/verifier.c in the Linux kernel before 4.5.5 does not properly maintain an fd data structure, which allows local users to gain privileges or cause a denial of service (use-after-free) via crafted BPF instructions that reference an incorrect file descriptor.

La función replace_map_fd_with_map_ptr en kernel/bpf/verifier.c en el kernel de Linux en versiones anteriores a 4.5.5 no mantiene correctamente una estructura de datos fd, lo que permite a usuarios locales obtener privilegios o provocar una denegación de servicio (uso después de liberación de memoria) a través de instrucciones BPF manipuladas que hacen referencia a un archivo descriptor incorrecto.

Linux kernel versions 4.4 and above where CONFIG_BPF_SYSCALL and kernel.unprivileged_bpf_disabled sysctl is not set to 1 allow for BPF to be abused for privilege escalation. Ubuntu 16.04 has all of these conditions met.

*Credits: N/A

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2016-05-03 CVE Published
2016-05-04 First Exploit
2016-05-06 CVE Reserved
2023-05-08 EPSS Updated
2024-08-06 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CAPEC

References (15)

URL	Tag	Source
http://www.openwall.com/lists/oss-security/2016/05/06/4	Mailing List
https://bugs.chromium.org/p/project-zero/issues/detail?id=808	Third Party Advisory
https://bugs.debian.org/823603	Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1334307	Issue Tracking
https://usn.ubuntu.com/2965-1
https://launchpad.net/bugs/1578705
http://changelogs.ubuntu.com/changelogs/pool/main/l/linux/linux_4.4.0-22.39/changelog
https://people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-4557.html
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8358b02bf67d3a5d8a825070e1aa73f25fb2e4c7

URL	Date	SRC
https://www.exploit-db.com/exploits/40759	2024-08-06
https://www.exploit-db.com/exploits/39772	2016-05-04

URL	Date	SRC

URL	Date	SRC
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8358b02bf67d3a5d8a825070e1aa73f25fb2e4c7	2023-01-17
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00044.html	2023-01-17
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.5.5	2023-01-17
https://github.com/torvalds/linux/commit/8358b02bf67d3a5d8a825070e1aa73f25fb2e4c7	2023-01-17

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 4.4 < 4.4.11 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.4 < 4.4.11"		-		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 4.5 < 4.5.5 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.5 < 4.5.5"		-		Affected