CVE-2018-0007

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 constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.

Affected Software

Extended Description

Command injection vulnerabilities typically occur when:

Many protocols and products have their own custom command language. While OS or shell command strings are frequently discovered and targeted, developers may not realize that these other command languages might also be vulnerable to attacks. Command injection is a common problem with wrapper programs.

Potential Mitigations

• Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
• When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
• Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/136.html
• https://cwe.mitre.org/data/definitions/15.html
• https://cwe.mitre.org/data/definitions/183.html
• https://cwe.mitre.org/data/definitions/248.html
• https://cwe.mitre.org/data/definitions/40.html
• https://cwe.mitre.org/data/definitions/43.html
• https://cwe.mitre.org/data/definitions/75.html
• https://cwe.mitre.org/data/definitions/76.html

References

• http://www.securitytracker.com/id/1040181
• https://kb.juniper.net/JSA10830
• http://www.securitytracker.com/id/1040181
• https://kb.juniper.net/JSA10830