CVE-2019-10691
Public on
Last Modified:
Description
The CVE Program describes this issue as:
The JSON encoder in Dovecot before 2.3.5.2 allows attackers to repeatedly crash the authentication service by attempting to authenticate with an invalid UTF-8 sequence as the username.
Statement
A flaw was found in the JSON encoder in dovecot, which an attacker could use to crash the application via usage of invalid UTF-8 characters in the login name during authentication or by using invalid UTF-8 sequence in email when OX push notification driver is enabled. The versions of dovecot shipped with Red Hat Enterprise Linux did not ship the vulnerable code and therefore were not affected by this flaw.
Additional information
- Bugzilla 1701216: dovecot: Mishandling invalid UTF-8 characters by JSON encoder leading to possible DoS attack.
- CWE-228: Improper Handling of Syntactically Invalid Structure
- FAQ: Frequently asked questions about CVE-2019-10691
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 | 7.5 | 7.5 |
Attack Vector | Network | Network |
Attack Complexity | Low | Low |
Privileges Required | None | None |
User Interaction | None | None |
Scope | Unchanged | Unchanged |
Confidentiality Impact | None | None |
Integrity Impact | None | None |
Availability Impact | High | High |
CVSS v3 Vector
Red Hat: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity,Availability
Technical Impact: Unexpected State; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU)
If an input is syntactically invalid, then processing the input could place the system in an unexpected state that could lead to a crash, consume available system resources or other unintended behaviors.
Frequently Asked Questions
Why is Red Hat's CVSS v3 score or Impact different from other vendors?
My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
What can I do if my product is listed as "Will not fix"?
What can I do if my product is listed as "Fix deferred"?
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?
My product is listed as "Out of Support Scope". What does this mean?
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
