External risk intelligence

Crypt::OpenSSL::PKCS12 Heap Out-of-Bounds Read Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2026-9265

This is a Perl module library used for processing PKCS#12 files. While it may be used by internet-facing applications to parse certificate data or handle encrypted payloads, it is a developer-focused library rather than a standalone appliance or service, making its direct public exposure dependent on how it is integrated into specific software deployments.

Out-of-bounds Read

Halo Surface Signal: 3 out of 5 — possibly public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This vulnerability affects the Crypt::OpenSSL::PKCS12 library used with Perl, potentially allowing unauthorized access to adjacent memory. While the direct impact is dependent on how this library is integrated into specific applications, it warrants attention to confirm relevance and exposure within our environments.

Heap memory could be read unexpectedly.
It involves a common Perl library for PKCS#12 processing.
Confirm if this library is in use and assess exposure.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted data to an application that uses a vulnerable version of the Crypt::OpenSSL::PKCS12 Perl module. The module's `print_attribute` function incorrectly handles UTF8STRING data, leading to a heap out-of-bounds read. This allows an attacker to influence adjacent memory, which could then be read by downstream functions, potentially leading to information disclosure or a crash.

No special access required.
Processing malicious PKCS12 data.
Information disclosure or denial of service.

Live Threat

Current exploitation, exposure, and threat context

When supported by the advisory, this vulnerability could affect the integrity and confidentiality of data processed by applications using the affected Perl module. Specifically, a heap out-of-bounds read can occur during the handling of UTF8STRING attributes within PKCS#12 files, potentially leading to the exposure of adjacent memory contents.

System data and sensitive information.
Heap out-of-bounds read in attribute handling.
Exposure of adjacent memory data.

Operational Fix

Recommended remediation, mitigation, and detection steps

The `Crypt::OpenSSL::PKCS12` Perl module, used for handling PKCS#12 files, is likely integrated into custom applications or development environments. Application owners and platform teams are probably responsible for assessing its use and impact within their specific deployments. The immediate priority is to identify all instances where this module is utilized, determine their business criticality and network exposure, and then confirm the accountable owner before planning any remediation.

Application owners and platform teams
Confirm module usage and exposure
Plan remediation based on risk

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is the Crypt::OpenSSL::PKCS12 module used for?

This is a library for the Perl programming language designed to handle PKCS#12 files, which are commonly used to store and transport cryptographic objects like certificates and private keys. Developers integrate this module into custom applications that need to parse, read, or process these encrypted or encoded identity-related files.

What does CVE-2026-9265 mean?

This vulnerability is an Out-of-Bounds Read (CWE-125). It occurs because the library's print_attribute function fails to properly add a NUL terminator to a buffer when copying data. Because the buffer lacks this boundary marker, the system continues reading memory beyond the intended area, potentially exposing sensitive adjacent data stored in the heap to the application.

How is this heap read vulnerability triggered?

An attacker triggers this by providing specially crafted PKCS#12 data to an application utilizing a vulnerable version of the library. It is not triggered by standard, well-formed files; the vulnerability specifically relies on the malformed UTF8STRING attribute path within the PKCS#12 structure to cause the memory overflow.

Is my system at risk from this CVE?

Halo Surface Signal notes that since this is a developer library, the risk depends on your specific software integrations rather than the library itself. If your application processes untrusted PKCS#12 files and is internet-facing, the risk is higher. Internal tools processing only trusted, local data have a significantly lower profile regarding direct exposure.

What should I do if I use Crypt::OpenSSL::PKCS12?

First, conduct an inventory to identify which applications include this Perl module. Once located, assess whether these applications process external, untrusted input files. If they do, plan to update to version 1.96 or later, where the string handling has been corrected to ensure proper memory termination.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.