CVE-2019-18197

Description

From CVE.org

In xsltCopyText in transform.c in libxslt 1.1.33, a pointer variable isn't reset under certain circumstances. If the relevant memory area happened to be freed and reused in a certain way, a bounds check could fail and memory outside a buffer could be written to, or uninitialized data could be disclosed.

Statement

Red Hat OpenStack consumes fixes from the base Red Hat Enterprise Linux Operating System. Therefore the libxslt package provided by Red Hat OpenStack has been marked as 'will not fix'.

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 Score7.57.57.5
Attack VectorNetworkNetworkNetwork
Attack ComplexityHighHighHigh
Privileges RequiredNoneNoneNone
User InteractionRequiredRequiredRequired
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

Vector

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

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

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

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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