CVE-2026-4647 is a vulnerability identified in the GNU Binutils Binary File Descriptor (BFD) library, a critical component used for handling various binary file formats including object files and executables. The flaw arises specifically when processing XCOFF (Extended Common Object File Format) object files that have been specially crafted to include an invalid relocation type value. The BFD library fails to properly validate this relocation type before using it, which results in an out-of-bounds read operation. This memory access violation can cause the affected tools that utilize the BFD library to crash unexpectedly, leading to denial-of-service conditions. Additionally, the out-of-bounds read may expose unintended memory contents, creating a limited information disclosure risk. The vulnerability is present in Red Hat Enterprise Linux 10 distributions that include the vulnerable version of the Binutils package. Exploitation requires local access and user interaction, as the attacker must provide a crafted XCOFF file for processing. The CVSS v3.1 base score is 6.1, reflecting a medium severity with low attack vector (local), low attack complexity, no privileges required, but requiring user interaction. The impact scope is unchanged, affecting only the local system. Currently, there are no known exploits in the wild, and no patches or mitigation links have been published at the time of disclosure. This vulnerability highlights the risks associated with processing untrusted binary files and the importance of input validation in low-level system libraries.

The primary impact of CVE-2026-4647 is denial-of-service through application or tool crashes when processing maliciously crafted XCOFF files, potentially disrupting development, build, or analysis workflows that rely on Binutils tools. The limited information disclosure risk could allow an attacker to glean some memory contents, which might aid in further attacks or reconnaissance, though the scope is limited. Since exploitation requires local access and user interaction, remote exploitation is not feasible, reducing the overall risk to network-facing services. However, in environments where users routinely process untrusted binary files—such as development, continuous integration, or security analysis systems—this vulnerability could be leveraged by malicious insiders or attackers with limited access to cause disruptions or gather sensitive information. The impact is largely confined to systems running Red Hat Enterprise Linux 10 with the vulnerable Binutils version, but similar environments using GNU Binutils with XCOFF support could be at risk if they share the same flaw. The absence of known exploits reduces immediate threat levels but does not eliminate the risk of future exploitation once the vulnerability is public.

To mitigate CVE-2026-4647, organizations should monitor Red Hat advisories closely and apply official patches or updates to the Binutils package as soon as they become available. Until patches are released, restrict processing of untrusted or unauthenticated XCOFF object files, especially in environments where users have local access to vulnerable systems. Implement strict file validation and scanning policies to detect and block malformed or suspicious binary files before they reach vulnerable tools. Limit user permissions to prevent unauthorized execution of tools that process binary files, reducing the risk of exploitation by unprivileged users. Employ application whitelisting and sandboxing techniques for development and build tools to contain potential crashes and prevent information leakage. Additionally, maintain robust monitoring and logging to detect abnormal crashes or memory access errors in affected tools, enabling rapid incident response. Finally, educate users about the risks of processing untrusted binaries and enforce policies to minimize user interaction with potentially malicious files.