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Verify Installed Package Files with debsums

Detect modified, corrupted or replaced system files on Debian and Ubuntu using package checksums.

LinuxpackagesdebsumssecurityMedium risk
Run sudo debsums -s to silently check every installed file against its package's md5sum and report only failures.

01Command

Command
$ sudo debsums -s

02What it does

debsums compares each file installed by a dpkg package against the md5 checksums stored in /var/lib/dpkg/info, so edited binaries, replaced libraries or accidental corruption surface as changed/failed lines. With -s it prints only files that fail verification, keeping the output readable. Files legitimately changed by configuration (conffiles) are handled, but freshly edited configs may need --changed or -e checks to review.

03Risk

RiskMedium risk
Requirementsdebsums package installed; Debian/Ubuntu (dpkg-based distros)
!Warning: debsums relies on checksums stored on the same machine, so a sophisticated rootkit could forge them — treat it as a corruption check, not proof of absence of malware.

04Undo

✓No undo needed — this command does not change persistent state.

05Sources

  • debsums(1) — Debian manpage
    Debian · community · 2026-09-17
    Evidence: Debian manpage documents debsums checking installed files against md5 checksums, with -s for reporting only errors
  • debsums(1) — Ubuntu manpage
    Ubuntu · community · 2026-09-17
    Evidence: Ubuntu manpage describes debsums verification against stored md5 sums and the --changed option

Last verified: 2026-09-19 · Category: Security & Privacy

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