CVE-2025-7545 Overview
CVE-2025-7545 is a heap-based buffer overflow [CWE-119] in GNU Binutils 2.45. The flaw resides in the copy_section function within binutils/objcopy.c. An attacker with local access and low privileges can trigger the overflow by supplying a crafted object file to objcopy. The GNU project has released a fix committed as 08c3cbe5926e4d355b5cb70bbec2b1eeb40c2944.
GNU Binutils ships with virtually every Linux distribution and underpins toolchain workflows for developers, build systems, and firmware engineers. The vulnerability has been publicly disclosed, though no in-the-wild exploitation has been confirmed.
Critical Impact
Local attackers can corrupt heap memory during objcopy operations, potentially causing crashes or memory corruption in build pipelines processing untrusted object files.
Affected Products
- GNU Binutils 2.45
- Linux distributions bundling the affected objcopy binary
- Siemens industrial products referencing Binutils (see advisories SSA-082556 and SSA-265688)
Discovery Timeline
- 2025-07-13 - CVE-2025-7545 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-7545
Vulnerability Analysis
The vulnerability sits in the copy_section routine of binutils/objcopy.c. This function copies section data from an input object file to an output file during operations such as stripping symbols, changing section flags, or converting object formats. Insufficient boundary validation during this copy operation allows data to be written beyond the allocated heap buffer.
Because objcopy is invoked routinely in software build systems, CI pipelines, and firmware processing workflows, malformed object files supplied to these workflows can trigger memory corruption. The attack requires local access and the ability to invoke objcopy against attacker-controlled input.
The exploit has been publicly disclosed through VulDB entry 316243 and Sourceware Bugzilla issue 33049, increasing the probability of proof-of-concept development.
Root Cause
The root cause is missing or insufficient bounds checking when copy_section writes section data into a heap-allocated destination buffer. When section metadata in the input file describes a size or offset inconsistent with the allocated buffer, the write operation exceeds the buffer boundary and corrupts adjacent heap memory.
Attack Vector
Exploitation requires local access with low privileges. An attacker crafts a malicious object file with manipulated section headers and induces a target user, build agent, or automated pipeline to process the file with objcopy. Successful triggering results in heap corruption, which typically manifests as a crash but may enable further memory manipulation depending on heap layout.
Refer to the Sourceware Bugzilla Issue #33049 for the reproduction details and attached test case.
Detection Methods for CVE-2025-7545
Indicators of Compromise
- Unexpected crashes or SIGSEGV events from objcopy processes on developer workstations or build servers
- objcopy invocations against object files originating from untrusted sources or external contributors
- Anomalous core dumps referencing heap corruption within binutils address space
Detection Strategies
- Inventory hosts running GNU Binutils 2.45 using package management queries such as dpkg -l binutils or rpm -q binutils
- Monitor CI/CD build agents for objcopy process failures correlated with new or externally sourced object files
- Deploy file integrity monitoring on /usr/bin/objcopy and related binutils components to detect tampering
Monitoring Recommendations
- Enable audit logging (auditd) for execve events targeting objcopy to capture command-line arguments and input paths
- Track EPSS scoring updates for CVE-2025-7545, currently at 0.254%, as public exploit availability may raise this over time
- Correlate build pipeline failures with newly ingested source archives or vendored binary artifacts
How to Mitigate CVE-2025-7545
Immediate Actions Required
- Apply the upstream patch 08c3cbe5926e4d355b5cb70bbec2b1eeb40c2944 from the Sourceware Git repository
- Upgrade to a patched Binutils release once distribution maintainers publish updated packages
- Restrict objcopy usage in automated pipelines to trusted, verified object file inputs
Patch Information
The fix is committed upstream as 08c3cbe5926e4d355b5cb70bbec2b1eeb40c2944 in the binutils-gdb repository. Siemens has published advisories SSA-082556 and SSA-265688 for affected industrial products. Linux distribution maintainers are expected to backport the patch to shipped Binutils 2.45 packages.
Workarounds
- Avoid processing untrusted object files with objcopy until the patch is applied
- Sandbox build processes using containers, seccomp profiles, or dedicated build accounts with minimal privileges
- Validate the origin and integrity of third-party object files before invoking Binutils utilities against them
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
