CVE-2026-57074 in XML::Bare
Summary
by MITRE • 07/16/2026
XML::Bare versions through 0.53 for Perl have an unbounded character lookahead.
The parserc_parse function attempts to check for multicharacter strings such as "<![CDATA" or element terminators such as ">" without checking that the offsets are within the buffer.
Truncated strings such as "<a/" can trigger an out-of-bounds read.
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Analysis
by VulDB Data Team • 07/17/2026
The vulnerability in XML::Bare versions through 0.53 represents a critical buffer overread condition that stems from insufficient input validation during XML parsing operations. This flaw exists within the parserc_parse function which processes XML documents without proper bounds checking on character offsets. The issue manifests when the parser encounters malformed or truncated XML sequences, particularly those involving incomplete element declarations such as "<a/" where the parser attempts to validate against patterns like CDATA sections or element terminators without verifying that the buffer boundaries have not been exceeded.
This vulnerability falls under the CWE-129 category of Improper Validation of Array Index and specifically relates to CWE-787 Out-of-bounds Read which occurs when a program reads data past the end of a valid buffer. The flaw enables attackers to craft malicious XML inputs that trigger memory access violations, potentially leading to information disclosure or system instability. The vulnerability is particularly concerning because it can be exploited through simple malformed input without requiring complex attack vectors, making it suitable for both denial-of-service attacks and potential information leakage scenarios.
The operational impact of this vulnerability extends beyond simple parsing failures as it represents a fundamental security flaw in the XML processing pipeline that could allow attackers to extract sensitive memory contents or cause application crashes. When truncated strings like "<a/" are processed, the parser attempts to access memory locations beyond the actual buffer boundaries, creating opportunities for adversaries to either gain unauthorized information access or disrupt normal application functionality through controlled memory access violations. This type of vulnerability aligns with ATT&CK technique T1210 Exploitation of Remote Services where attackers leverage parsing flaws in network services to achieve their objectives.
Mitigation strategies should focus on immediate version updates to XML::Bare 0.54 or later which contain the necessary bounds checking fixes. Organizations should also implement input validation measures including XML schema validation, content filtering, and regular security scanning of XML processing components. Additionally, deploying intrusion detection systems that monitor for unusual parsing patterns and implementing proper memory protection mechanisms such as stack canaries and address space layout randomization can help reduce the attack surface. The vulnerability demonstrates the importance of rigorous input validation in parsing libraries and highlights how seemingly simple buffer management issues can create significant security risks in widely used software components.