CVE Vulnerabilities

CVE-2018-0007

Improper Restriction of Operations within the Bounds of a Memory Buffer

Published: Jan 10, 2018 | Modified: Aug 24, 2020
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
10 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

An unauthenticated network-based attacker able to send a maliciously crafted LLDP packet to the local segment, through a local segment broadcast, may be able to cause a Junos device to enter an improper boundary check condition allowing a memory corruption to occur, leading to a denial of service. Further crafted packets may be able to sustain the denial of service condition. Score: 6.5 MEDIUM (CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) Further, if the attacker is authenticated on the target device receiving and processing the malicious LLDP packet, while receiving the crafted packets, the attacker may be able to perform command or arbitrary code injection over the target device thereby elevating their permissions and privileges, and taking control of the device. Score: 7.8 HIGH (CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) An unauthenticated network-based attacker able to send a maliciously crafted LLDP packet to one or more local segments, via LLDP proxy / tunneling agents or other LLDP through Layer 3 deployments, through one or more local segment broadcasts, may be able to cause multiple Junos devices to enter an improper boundary check condition allowing a memory corruption to occur, leading to multiple distributed Denials of Services. These Denials of Services attacks may have cascading Denials of Services to adjacent connected devices, impacts network devices, servers, workstations, etc. Further crafted packets may be able to sustain these Denials of Services conditions. Score 6.8 MEDIUM (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H) Further, if the attacker is authenticated on one or more target devices receiving and processing these malicious LLDP packets, while receiving the crafted packets, the attacker may be able to perform command or arbitrary code injection over multiple target devices thereby elevating their permissions and privileges, and taking control multiple devices. Score: 7.8 HIGH (CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H) Affected releases are Juniper Networks Junos OS: 12.1X46 versions prior to 12.1X46-D71; 12.3 versions prior to 12.3R12-S7; 12.3X48 versions prior to 12.3X48-D55; 14.1 versions prior to 14.1R8-S5, 14.1R9; 14.1X53 versions prior to 14.1X53-D46, 14.1X53-D50, 14.1X53-D107; 14.2 versions prior to 14.2R7-S9, 14.2R8; 15.1 versions prior to 15.1F2-S17, 15.1F5-S8, 15.1F6-S8, 15.1R5-S7, 15.1R7; 15.1X49 versions prior to 15.1X49-D90; 15.1X53 versions prior to 15.1X53-D65; 16.1 versions prior to 16.1R4-S6, 16.1R5; 16.1X65 versions prior to 16.1X65-D45; 16.2 versions prior to 16.2R2; 17.1 versions prior to 17.1R2. No other Juniper Networks products or platforms are affected by this issue.

Weakness

The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.

Affected Software

Name Vendor Start Version End Version
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46
Junos Juniper 12.1x46 12.1x46

Extended Description

Certain languages allow direct addressing of memory locations and do not automatically ensure that these locations are valid for the memory buffer that is being referenced. This can cause read or write operations to be performed on memory locations that may be associated with other variables, data structures, or internal program data. As a result, an attacker may be able to execute arbitrary code, alter the intended control flow, read sensitive information, or cause the system to crash.

Potential Mitigations

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer.

  • Be wary that a language’s interface to native code may still be subject to overflows, even if the language itself is theoretically safe.

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • Examples include the Safe C String Library (SafeStr) by Messier and Viega [REF-57], and the Strsafe.h library from Microsoft [REF-56]. These libraries provide safer versions of overflow-prone string-handling functions.

  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.

  • D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.

  • Consider adhering to the following rules when allocating and managing an application’s memory:

  • Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.

  • Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.

  • For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].

  • Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX [REF-60] [REF-61]. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment.

  • For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND [REF-1336].

References