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Memory corruption issues is Cloudflare zlib implementation

Moderate
mskowroncf published GHSA-vww9-j87r-4cqh Jan 4, 2024

Package

zlib (C)

Affected versions

<8352d108c05db1bdc5ac3bdf834dad641694c13c

Patched versions

8352d108c05db1bdc5ac3bdf834dad641694c13c

Description

Impact

Cloudflare version of zlib library was found to be vulnerable to memory corruption issues affecting the deflation algorithm implementation (deflate.c). The issues resulted from improper input validation and heap-based buffer overflow.
A local attacker could exploit the problem during compression using a crafted malicious file potentially leading to denial of service of the software.

Patches

The issue has been patched in commit [8352d10].

References

CVE-2023-6992

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Local
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L

CVE ID

CVE-2023-6992

Weaknesses

Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Learn more on MITRE.

Heap-based Buffer Overflow

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Learn more on MITRE.

Buffer Over-read

The product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations after the targeted buffer. Learn more on MITRE.

Credits