CVE-2022-22234

An Improper Preservation of Consistency Between Independent Representations of Shared State vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows a locally authenticated attacker with low privileges to cause a Denial of Service (DoS). If the device is very busy for example while executing a series of show commands on the CLI one or more SFPs might not be detected anymore. The system then changes its state to unplugged which is leading to traffic impact and at least a partial DoS. Once the system is less busy the port states return to their actual value. Indicators of compromise are log messages about unplugged SFPs and corresponding syspld messages without any physical or environmental cause. These can be checked by issuing the following commands: user@device# show log messages | match unplugged %PFE-6: fpc0 sfp-0/1/2 SFP unplugged %PFE-6: fpc0 sfp-0/1/3 SFP unplugged The following log messages will also be seen when this issue happens: fpc0 Error tvp_drv_syspld_read: syspld read failed for address fpc0 Error[-1]:tvp_optics_presence_get - Syspld read failed for port <pic/port> fpc0 optics pres failed(-1) for pic port fpc0 tvp_drv_syspld_read: i2c access retry count 200 This issue affects Juniper Networks Junos OS on EX2300 Series, EX3400 Series: All versions prior to 18.4R3-S11; 19.1 versions prior to 19.1R3-S9; 19.2 versions prior to 19.2R1-S9, 19.2R3-S5; 19.3 versions prior to 19.3R3-S6; 19.4 versions prior to 19.4R2-S7, 19.4R3-S8; 20.1 versions prior to 20.1R3-S4; 20.2 versions prior to 20.2R3-S4; 20.3 versions prior to 20.3R3-S4; 20.4 versions prior to 20.4R3-S3; 21.1 versions prior to 21.1R3-S1; 21.2 versions prior to 21.2R3; 21.3 versions prior to 21.3R2; 21.4 versions prior to 21.4R2.

Weakness

The product has or supports multiple distributed components or sub-systems that are each required to keep their own local copy of shared data - such as state or cache - but the product does not ensure that all local copies remain consistent with each other.

Affected Software

Extended Description

In highly distributed environments, or on systems with distinct physical components that operate independently, there is often a need for each component to store and update its own local copy of key data such as state or cache, so that all components have the same “view” of the overall system and operate in a coordinated fashion. For example, users of a social media service or a massively multiplayer online game might be using their own personal computers while also interacting with different physical hosts in a globally distributed service, but all participants must be able to have the same “view” of the world. Alternately, a processor’s Memory Management Unit (MMU) might have “shadow” MMUs to distribute its workload, and all shadow MMUs are expected to have the same accessible ranges of memory. In such environments, it becomes critical for the product to ensure that this “shared state” is consistently modified across all distributed systems. If state is not consistently maintained across all systems, then critical transactions might take place out of order, or some users might not get the same data as other users. When this inconsistency affects correctness of operations, it can introduce vulnerabilities in mechanisms that depend on consistent state.

References

• https://kb.juniper.net/JSA69890
• https://kb.juniper.net/JSA69890