CVE-2020-10968
Description
A flaw was found in jackson-databind 2.x prior to version 2.9.10.4. The interaction between serialization gadgets and typing is mishandled in the bus-proxy. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Statement
While OpenShift Container Platform's elasticsearch plugins do ship the vulnerable component, it doesn't do any of the unsafe things described in https://access.redhat.com/solutions/3279231. We may update the jackson-databind dependency in a future release.
Red Hat OpenStack Platform ships OpenDaylight, which contains the vulnerable jackson-databind. However, OpenDaylight does not expose jackson-databind in a way that would make it vulnerable, lowering the impact of the vulnerability for OpenDaylight. As such, Red Hat will not be providing a fix for OpenDaylight at this time.
Red Hat Satellite 6 does not enable polymorphic deserialization which is a required configuration for the vulnerability to be used. We may update the jackson-databind dependency in a future release.
The PKI module as shipped in Red Hat Enterprise Linux 8 does not enable polymorphic deserialization which is a required configuration for the vulnerability to be used, lowering the impact of the vulnerability for the Product. We may update the jackson-databind dependency in a future release.
Mitigation
The following conditions are needed for an exploit, we recommend avoiding all if possible
* Deserialization from sources you do not control
* `enableDefaultTyping()`
* `@JsonTypeInfo using `id.CLASS` or `id.MINIMAL_CLASS`
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.8 | 8.8 | 8.8 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | Required | Required | Required |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | High | High |
| Integrity Impact | High | High | High |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
