CVE-2020-24616
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ImportantImportant ImpactWhat does this mean?
Description
A flaw was found in FasterXML jackson-databind 2.x in versions prior to 2.9.10.6. The interaction between serialization gadgets and typing are mishandled. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Statement
The Red Hat JBoss Enterprise Application Platform 7 does ship the vulnerable component but has a mandatory whitelist which blocks all wicked serializing classes and does not enable the unsafe conditions needed to exploit.
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.
The PKI module as shipped in Red Hat Enterprise Linux 8 and Red Hat Satellite 6 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.
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 6.6 and later ship Candlepin with an already fixed version of jackson-databind.
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`
* avoid br.com.anteros.dbcp in the classpath
Additional information
- Bugzilla 1872707: jackson-databind: mishandles the interaction between serialization gadgets and typing, related to br.com.anteros.dbcp.AnterosDBCPDataSource
- CWE-96: Improper Neutralization of Directives in Statically Saved Code ('Static Code Injection')
- FAQ: Frequently asked questions about CVE-2020-24616
Common Vulnerability Scoring System (CVSS) Score Details
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).
The following CVSS metrics and score provided are preliminary and subject to review.
| Red Hat | NVD | |
|---|---|---|
CVSS v3 Base Score | 8.1 | 8.1 |
Attack Vector | Network | Network |
Attack Complexity | High | High |
Privileges Required | None | None |
User Interaction | None | None |
Scope | Unchanged | Unchanged |
Confidentiality Impact | High | High |
Integrity Impact | High | High |
Availability Impact | High | High |
CVSS v3 Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Red Hat CVSS v3 Score Explanation
The AC should be High because there are sufficient factors beyond the attacker's control:
1. Accepts JSON content sent by an untrusted client
2. Has the “gadget” class br.com.anteros.dbcp.AnterosDBCPDataSource in the Java classpath: and specifically, the class works with Jackson
3. Enable polymorphic type handling: objectMapper.enableDefaultTyping();
4. Use a version of Jackson that does not (yet) block “gadget” class br.com.anteros.dbcp.AnterosDBCPDataSource
The vulnerability can be exploited only if all of these conditions are true. [1] This set of conditions, we feel reflects AC:H rather than AC:L.
[1] https://medium.com/@cowtowncoder/on-jackson-cves-dont-panic-here-is-what-you-need-to-know-54cd0d6e8062
Frequently Asked Questions
Why is Red Hat's CVSS v3 score or Impact different from other vendors?
For more information, see https://access.redhat.com/solutions/762393.
My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
- "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
- The term "Affected" means that our Analysis team has determined that this product, such as Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to address this issue in the near future. This includes all minor releases of this product unless noted otherwise in the Statement text.
What can I do if my product is listed as "Will not fix"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
- Apply a mitigation (if one exists).
- Open a support case to request a prioritization of releasing a fix for this vulnerability.
What can I do if my product is listed as "Fix deferred"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Apply a mitigation (if one exists).
- Open a support case to request a prioritization of releasing a fix for this vulnerability.
- Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.
What is a mitigation?
I have a Red Hat product but it is not in the above list, is it affected?
Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?
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