Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2017-3631)

high Nessus Plugin ID 104167
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

The remote Oracle Linux host is missing one or more security updates.

Description

The remote Oracle Linux 6 / 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2017-3631 advisory.

- Linux kernel: Exploitable memory corruption due to UFO to non-UFO path switch. When building a UFO packet with MSG_MORE __ip_append_data() calls ip_ufo_append_data() to append. However in between two send() calls, the append path can be switched from UFO to non-UFO one, which leads to a memory corruption. In case UFO packet lengths exceeds MTU, copy = maxfraglen - skb->len becomes negative on the non-UFO path and the branch to allocate new skb is taken. This triggers fragmentation and computation of fraggap = skb_prev->len - maxfraglen. Fraggap can exceed MTU, causing copy = datalen - transhdrlen - fraggap to become negative. Subsequently skb_copy_and_csum_bits() writes out-of-bounds. A similar issue is present in IPv6 code. The bug was introduced in e89e9cf539a2 ([IPv4/IPv6]: UFO Scatter-gather approach) on Oct 18 2005. (CVE-2017-1000112)

- The ip6_find_1stfragopt function in net/ipv6/output_core.c in the Linux kernel through 4.12.3 allows local users to cause a denial of service (integer overflow and infinite loop) by leveraging the ability to open a raw socket. (CVE-2017-7542)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://linux.oracle.com/errata/ELSA-2017-3631.html

Plugin Details

Severity: High

ID: 104167

File Name: oraclelinux_ELSA-2017-3631.nasl

Version: 3.15

Type: local

Agent: unix

Published: 10/26/2017

Updated: 9/8/2021

Dependencies: linux_alt_patch_detect.nasl, ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2017-1000112

VPR

Risk Factor: Critical

Score: 9.6

CVSS v2

Risk Factor: Medium

Base Score: 6.9

Temporal Score: 5.7

Vector: AV:L/AC:M/Au:N/C:C/I:C/A:C

Temporal Vector: E:F/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7

Temporal Score: 6.5

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:F/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:oracle:linux:6, cpe:/o:oracle:linux:7, p-cpe:/a:oracle:linux:kernel-uek, p-cpe:/a:oracle:linux:kernel-uek-debug, p-cpe:/a:oracle:linux:kernel-uek-debug-devel, p-cpe:/a:oracle:linux:kernel-uek-devel, p-cpe:/a:oracle:linux:kernel-uek-doc, p-cpe:/a:oracle:linux:kernel-uek-firmware

Required KB Items: Host/OracleLinux, Host/RedHat/release, Host/RedHat/rpm-list, Host/local_checks_enabled

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/24/2017

Vulnerability Publication Date: 7/19/2017

Exploitable With

Core Impact

Metasploit (Linux Kernel UDP Fragmentation Offset (UFO) Privilege Escalation)

Reference Information

CVE: CVE-2017-7542, CVE-2017-1000112