CVE-2018-13845 in HTSlib
Summary
by MITRE
An issue has been found in HTSlib 1.8. It is a buffer over-read in sam_parse1 in sam.c.
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Analysis
by VulDB Data Team • 04/06/2023
The vulnerability identified as CVE-2018-13845 represents a critical buffer over-read flaw within HTSlib version 1.8, specifically affecting the sam_parse1 function in the sam.c source file. This issue arises from insufficient input validation during the parsing of SAM (Sequence Alignment/Map) format files, which are fundamental data structures in genomic sequence analysis. The buffer over-read occurs when the library attempts to process malformed or maliciously crafted SAM records, leading to potential memory corruption and unpredictable behavior. Such vulnerabilities are particularly concerning in bioinformatics environments where large-scale genomic data processing is routine and security considerations are paramount for maintaining data integrity and system stability.
The technical root cause of this vulnerability stems from inadequate bounds checking within the sam_parse1 function, which processes SAM file records containing genomic sequence alignments. When encountering malformed data structures or unexpected field lengths in SAM format entries, the parsing routine fails to properly validate buffer boundaries before reading memory locations. This condition allows an attacker to craft specially formatted SAM records that trigger memory access beyond allocated buffer limits. The vulnerability manifests as a classic buffer over-read scenario where the program attempts to read data from memory locations that were not properly allocated for the current operation, potentially exposing sensitive information or causing application crashes.
The operational impact of CVE-2018-13845 extends beyond simple application instability to encompass potential security risks in genomic data processing pipelines. Systems utilizing HTSlib for variant calling, alignment analysis, or genomic data management may become vulnerable to denial of service attacks or information disclosure when processing untrusted SAM inputs. In laboratory environments where genomic data integrity is crucial for research and clinical applications, this vulnerability could compromise the reliability of sequence analysis workflows. The vulnerability aligns with CWE-125, which describes out-of-bounds read conditions, and represents a significant concern for organizations following ATT&CK framework tactics related to execution and privilege escalation through software supply chain compromises.
Mitigation strategies for this vulnerability require immediate patching of HTSlib installations to versions that address the buffer over-read issue in sam_parse1. Organizations should implement comprehensive input validation for all SAM file processing operations and consider deploying sandboxed environments for handling untrusted genomic data. Additionally, regular security audits of bioinformatics toolchains and dependency management practices should be established to prevent similar vulnerabilities from emerging in other components of genomic analysis pipelines. The remediation process should include thorough testing of patched libraries in production environments to ensure that the fix does not introduce regressions in legitimate genomic data processing workflows while maintaining compliance with industry standards for secure software development practices.