Quick answers
- Is CVE-2026-54581 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-54581 being exploited in the wild.
- How severe is CVE-2026-54581?
- Informational severity, with a CVSS score of 6.5, published 17 September 2026.
- Which products and versions are affected?
- MidnightBSD Mport before 2.7.8.
- Is there a fix for CVE-2026-54581?
- A patch was published on 2026-09-17: Version 2.7.8 includes the fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-54581 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-54581?
- Check whether you run MidnightBSD Mport at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a hash verification bypass in the mport_fetch_bootstrap_index() function in libmport/fetch.c. When bootstrap index hash verification fails (due to a missing or invalid hash), the failure path incorrectly returns success instead of propagating the fatal error to the caller. The root cause is that on hash verification failure, the function calls mport_call_msg_cb() to log the error but does not set result = MPORT_ERR_FATAL before returning, leaving result in its previous MPORT_OK state from the successful file fetch. A network attacker or compromised mirror can exploit this by serving an altered bootstrap index, which mport will proceed to use without detecting tampering. The fix, deployed in version 2.7.8, ensures the fatal error status is properly set and propagated when hash verification fails.
Affected products
- MidnightBSD mport before 2.7.8
Timeline
- 2026-09-17: disclosed
- 2026-09-17: patched: Version 2.7.8 includes the fix