CVE-2020-8244
Description
From CVE.org
A buffer over-read vulnerability exists in bl <4.0.3, <3.0.1, <2.2.1, and <1.2.3 which could allow an attacker to supply user input (even typed) that if it ends up in consume() argument and can become negative, the BufferList state can be corrupted, tricking it into exposing uninitialized memory via regular .slice() calls.
Statement
Red Hat OpenShift Container Platform 4 delivers the kibana package where the nodejs-bl module is used, but during the update to container first (to openshift4/ose-logging-kibana6) the dependency was removed and hence kibana package is marked as wontfix. This may be fixed in the future.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | 6.5 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | None | None | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | Low | Low | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | Low | Low | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Red Hat CVSS v3 Score Explanation
Proposed changes to current CVSSv3 scoring: PR:L -> PR:N C:H -> C:L A:H -> A:L
To exploit this vulnerability the attacker does't need special privileges, it is enough if user input (even typed) ends up in consume() argument and can become negative, then the BufferList module state can be corrupted. Successful exploitation can leads to getting access to some restricted information, but the attacker doesn't have control over what information is obtained. In the other scenario even a large buffer allocation shouldn't lead to DoS, but could reduce the application performance. Hence proposing a change to below metrics: Privileges required (PR) from Low to None Confidentiality (C) from High to Low Availability (A) from High to Low
We consider this as a Moderate impact flaw.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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