CVE-2023-25193 : Security Advisory and Response

This CVE record was published on February 4, 2023, by MITRE. The vulnerability identified as CVE-2023-25193 is related to hb-ot-layout-gsubgpos.hh in HarfBuzz through version 6.0.0. This vulnerability enables attackers to trigger O(n^2) growth by exploiting consecutive marks during the process of looking back for base glyphs when attaching marks.

Understanding CVE-2023-25193

This section will delve into the details of CVE-2023-25193, shedding light on the vulnerability's nature and impact.

What is CVE-2023-25193?

The CVE-2023-25193 vulnerability is present in HarfBuzz up to version 6.0.0, specifically in the hb-ot-layout-gsubgpos.hh component. Attackers can exploit this flaw to trigger a potentially dangerous O(n^2) growth by utilizing consecutive marks during the base glyph attachment process.

The Impact of CVE-2023-25193

This vulnerability could pose a significant threat as it allows for the potential escalation of resources and could be potentially abused by malicious actors to compromise systems running affected versions of HarfBuzz.

Technical Details of CVE-2023-25193

In this section, we will explore the technical aspects of CVE-2023-25193, including the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability in hb-ot-layout-gsubgpos.hh in HarfBuzz allows for a specific type of growth vulnerability when handling consecutive marks during base glyph attachment, potentially leading to significant resource escalation.

Affected Systems and Versions

The affected component, hb-ot-layout-gsubgpos.hh in HarfBuzz up to version 6.0.0, is susceptible to the CVE-2023-25193 vulnerability, impacting systems that utilize these versions of the software.

Exploitation Mechanism

By manipulating the process of looking back for base glyphs when attaching marks in HarfBuzz, attackers can exploit consecutive marks to trigger a dangerous O(n^2) growth, potentially leading to resource exhaustion or denial of service.

Mitigation and Prevention

To address CVE-2023-25193 and protect systems from potential exploitation, certain mitigation and prevention measures need to be taken.

Immediate Steps to Take

It is advisable to update HarfBuzz to a patched version that addresses the CVE-2023-25193 vulnerability. Additionally, implementing robust security measures and limiting exposure to potentially malicious entities can help mitigate the risk of exploitation.

Long-Term Security Practices

To enhance overall system security, organizations should prioritize regular software updates, security audits, and vulnerability assessments. Training staff on secure coding practices and promoting a culture of security awareness can also contribute to long-term resilience against threats.

Patching and Updates

Users and organizations utilizing HarfBuzz should regularly monitor for security advisories and promptly apply patches provided by the software vendor. Keeping software up to date with the latest security fixes is crucial in mitigating the risk of exploitation from known vulnerabilities.