CVE-2022-43552

Description

A vulnerability was found in curl. In this issue, curl can be asked to tunnel all protocols virtually it supports through an HTTP proxy. HTTP proxies can deny these tunnel operations using an appropriate HTTP error response code. When getting denied to tunnel the specific SMB or TELNET protocols, curl can use a heap-allocated struct after it has been freed and shut down the code path in its transfer.

Statement

Potential successful exploitation will cause the curl to crash, which generates a low impact to the environment where the curl is used. Additionally, exploitation depends on the conditions that are out of the attacker's control, like usage of specific protocols (SMB or TELNET) and HTTP proxy tunnels at the same time. Due to these facts, this vulnerability has been classified as a Low severity issue.

Mitigation

Avoid using the SMB and TELNET protocols.

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 HatNVDcve.org
Base Score5.95.95.9
Attack VectorNetworkNetworkNetwork
Attack ComplexityHighHighHigh
Privileges RequiredNoneNoneNone
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneNone
Integrity ImpactNoneNoneNone
Availability ImpactHighHighHigh

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

NVD: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Red Hat CVSS v3 Score Explanation

Attack complexity is marked as High because a successful attack depends on conditions beyond the attacker's control and by using any fuzzing tools the attacker can not compromise the system easily.

Understanding the Weakness (CWE)

Integrity

Technical Impact: Modify Memory

The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.

Confidentiality

Technical Impact: Read Memory

Read operations on freed memory can sometimes leak sensitive information instead of causing a crash

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Frequently Asked Questions

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