Issue summary: Writing large, newline-free data into a BIO chain using the line-buffering filter where the next BIO performs short writes can trigger a heap-based out-of-bounds write. Impact summary: This out-of-bounds write can cause memory corruption which typically results in a crash, leading to Denial of Service for an application. The line-buffering BIO filter (BIO_f_linebuffer) is not used by default in TLS/SSL data paths. In OpenSSL command-line applications, it is typically only pushed onto stdout/stderr on VMS systems. Third-party applications that explicitly use this filter with a BIO chain that can short-write and that write large, newline-free data influenced by an attacker would be affected. However, the circumstances where this could happen are unlikely to be under attacker control, and BIO_f_linebuffer is unlikely to be handling non-curated data controlled by an attacker. For that reason the issue was assessed as Low severity. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the BIO implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.7, requiring local system access to exploit but requires specific conditions to be met without requiring user interaction requiring only low-level privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 1 product from openssl organizations running these solutions should prioritize assessment and patching.
Reported in 2026, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2026-01-27T16:16:15.900
2026-06-17T09:58:39.407
Modified
CVSSv3.1: 4.7 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | openssl | openssl | < 1.0.2zn | Yes |
| Application | openssl | openssl | < 1.1.1ze | Yes |
| Application | openssl | openssl | < 3.0.19 | Yes |
| Application | openssl | openssl | < 3.3.6 | Yes |
| Application | openssl | openssl | < 3.4.4 | Yes |
| Application | openssl | openssl | < 3.5.5 | Yes |
| Application | openssl | openssl | < 3.6.1 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For openssl's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.