CVE-2026-54576
mport package installation has symlink TOCTOU in chown and chmod handling
mport is the MidnightBSD Package Manager. Prior to 2.7.8, do_actual_install() in libmport/bundle_read_install_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with a symlink before privileged ownership or mode changes were applied, redirecting those changes to an attacker-selected path and compromising filesystem integrity or permissions. This issue is fixed in version 2.7.8.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
5.8
mport package installation has symlink TOCTOU in chown and chmod handling
mport is the MidnightBSD Package Manager. Prior to 2.7.8, do_actual_install() in libmport/bundle_read_install_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with a symlink before privileged ownership or mode changes were applied, redirecting those changes to an attacker-selected path and compromising filesystem integrity or permissions. This issue is fixed in version 2.7.8.
- Record
CVE-2026-54576- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-59, CWE-367
- Updated
- 2026-11-02
EUVDEUVD-2026-82329
5.8
mport is the MidnightBSD Package Manager. Prior to 2.7.8, do_actual_install() in libmport/bundle_read_install_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with a symlink before privileged ownership or mode changes were applied, redirecting those changes to an attacker-selected path and compromising filesystem integrity or permissions. This issue is fixed in version 2.7.8.
- Record
EUVD-2026-82329- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N - Updated
- 2026-11-02
NVD
5.8
mport is the MidnightBSD Package Manager. Prior to 2.7.8, do_actual_install() in libmport/bundle_read_install_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with a symlink before privileged ownership or mode changes were applied, redirecting those changes to an attacker-selected path and compromising filesystem integrity or permissions. This issue is fixed in version 2.7.8.
- Record
CVE-2026-54576- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-59, CWE-367
- Updated
- 2026-11-02
OSV
5.8
mport package installation has symlink TOCTOU in chown and chmod handling
mport is the MidnightBSD Package Manager. Prior to 2.7.8, do_actual_install() in libmport/bundle_read_install_pkg.c used path-based lstat(), chown(), stat(), and chmod() operations while installing package files. A local attacker with write access to a target directory could replace a checked file with a symlink before privileged ownership or mode changes were applied, redirecting those changes to an attacker-selected path and compromising filesystem integrity or permissions. This issue is fixed in version 2.7.8.
- Record
CVE-2026-54576- CVSS 4.0
- 5.8 Medium
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-367, CWE-59
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-54576 is a medium vulnerability (CVSS 5.8) in Midnightbsd Mport, published September 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.10%, the 1st percentile. No source names a fixed version.
References
github.com/MidnightBSD/mport/security/advisories/GHSA-23g3-7fv3-3ccf
github.com/MidnightBSD/mport/pull/150
github.com/MidnightBSD/mport/commit/4676ac05b1056b54a3d38d03ae8a478bf12c9abe
github.com/MidnightBSD/mport/releases/tag/2.7.8
github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54576.json
nvd.nist.gov/vuln/detail/CVE-2026-54576