Linux Kernel up to 4.5.4 BPF Instruction kernel/bpf/verifier.c replace_map_fd_with_map_ptr use after free

CVSS Meta Temp Score
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5.8$0-$5k0.00

A vulnerability was found in Linux Kernel up to 4.5.4 (Operating System). It has been declared as problematic. This vulnerability affects the function replace_map_fd_with_map_ptr of the file kernel/bpf/verifier.c of the component BPF Instruction. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect availability. CVE summarizes:

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.

The bug was discovered 04/26/2016. The weakness was shared 05/23/2016 (Website). The advisory is shared for download at github.com. This vulnerability was named CVE-2016-4557 since 05/06/2016. The exploitation appears to be easy. The attack needs to be approached locally. No form of authentication is required for a successful exploitation. Technical details and also a public exploit are known.

It is possible to download the exploit at exploit-db.com. It is declared as highly functional. The vulnerability was handled as a non-public zero-day exploit for at least 10 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 91084 (Ubuntu 16.04 LTS : linux-raspi2 vulnerabilities (USN-2965-3)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196463 (Ubuntu Security Notification for Linux Vulnerabilities (USN-2965-1)).

Upgrading to version 4.5.5 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (91084) and Exploit-DB (40759). The entries 81364, 81365, 81366 and 81378 are related to this item.

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CPE 2.3info

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CVSSv4info

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CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 4.0
VulDB Temp Score: 3.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Highly functional
Download: 🔍

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Nessus ID: 91084
Nessus Name: Ubuntu 16.04 LTS : linux-raspi2 vulnerabilities (USN-2965-3)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 830125
OpenVAS Name: Ubuntu Update for linux-raspi2 USN-2965-3
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

MetaSploit ID: bpf_priv_esc.rb
MetaSploit Name: Linux BPF Local Privilege Escalation
MetaSploit File: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 4.5.5
Patch: git.kernel.org

Timelineinfo

04/26/2016 🔍
05/06/2016 +10 days 🔍
05/06/2016 +0 days 🔍
05/12/2016 +6 days 🔍
05/23/2016 +11 days 🔍
05/23/2016 +0 days 🔍
05/24/2016 +1 days 🔍
08/22/2022 +2281 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 8358b02bf67d3a5d8a825070e1aa73f25fb2e4c7
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-4557 (🔍)
scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 05/24/2016 11:55
Updated: 08/22/2022 08:52
Changes: 05/24/2016 11:55 (79), 07/17/2019 18:55 (8), 08/22/2022 08:52 (5)
Complete: 🔍

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