CVE-2005-3382
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedMultiple interpretation error in Sophos 3.91 with the 2.28.4 engine allows remote attackers to bypass virus scanning via a file such as BAT, HTML, and EML with an "MZ" magic byte sequence which is normally associated with EXE, which causes the file to be treated as a safe type that could still be executed as a dangerous file type by applications on the end system, as demonstrated by a "triple headed" program that contains EXE, EML, and HTML content, aka the "magic byte bug."
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceSophos Antivirus 3.91 with engine 2.28.4 misidentifies file types based on magic byte detection. Attackers embed executable code with 'MZ' headers (normally EXE) inside BAT, HTML, or EML files, causing the antivirus to classify them as safe file types and skip scanning, while the embedded executable code can still run on endpoint systems.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 3.91_engine_2.28.4CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Authentication
- None
- Confidentiality
- None
- Integrity
- Partial
- Availability
- None
AV:N/AC:L/Au:N/C:N/I:P/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Identify Sophos Anti Virus installation versionCheck the installed Sophos Anti Virus version through the application properties, About dialog, or version information in the program filesAffected if Version equals 3.91 exactly (3.91_engine_2.28.4)
-
Confirm engine versionLocate and read the Sophos engine version information, typically found in engine-related files or the antivirus interfaceAffected if Engine version is 2.28.4 exactly
-
Verify file type detection methodExamine Sophos configuration or scanning settings to confirm the file type identification relies on magic byte/header detection rather than content-based analysisAffected if Magic byte detection is the active file typing method (this is the default vulnerable behavior)
-
Test embedded executable detection (optional validation)Create a test file containing an MZ header (EXE signature) embedded within a BAT, HTML, or EML file format and attempt to scan it to see if the executable content is detected or skippedAffected if The embedded executable code is not detected or the file is classified as safe based solely on the container file type
If Sophos Anti Virus version 3.91 with engine 2.28.4 is installed and uses magic byte-based file type detection (the default configuration), the environment is affected by this vulnerability.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpgrade Sophos to a version that performs content-based analysis beyond magic byte detection, or augment with additional email gateway and endpoint controls to detect and block multi-format file attachments.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2005-3382 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2005-3382 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data