CVE-2021-30997
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 · uneditedA S/MIME issue existed in the handling of encrypted email. This issue was addressed by not automatically loading some MIME parts. This issue is fixed in iOS 15.2 and iPadOS 15.2. An attacker may be able to recover plaintext contents of an S/MIME-encrypted e-mail.
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 · high confidenceA vulnerability in iOS/iPadOS allowed automatic loading of certain MIME parts within S/MIME encrypted emails, bypassing the encryption protection and enabling attackers to recover plaintext contents of supposedly encrypted messages.
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< 15.2< 15.2CVSS 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
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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.
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Check iOS/iPadOS versionOpen Settings > General > About > Version, or check via MDM/Apple Configurator, or use iTunes/Finder when device is connectedAffected if Version number is below 15.2 (e.g., 15.1, 15.0, 14.x, etc.)
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Verify S/MIME configurationGo to Settings > Mail > Accounts > select email account > Account > Advanced > S/MIME. Check if 'Sign' or 'Encrypt' options are enabledAffected if S/MIME is enabled (either Sign or Encrypt toggles are on) and the iOS/iPadOS version is below 15.2
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Check for installed S/MIME certificatesGo to Settings > General > About > Certificate Trust Settings, or check in Settings > Passwords & Accounts > Account > Advanced > S/MIME for active certificatesAffected if An S/MIME certificate is installed and trusted, and the device runs iOS/iPadOS below 15.2
Device is affected if running iOS/iPadOS version below 15.2 AND has S/MIME enabled with an active certificate for encrypted email, as the vulnerability allows plaintext recovery from encrypted MIME parts.
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.
dbcve · scoped15.2
Update affected iOS/iPadOS devices to version 15.2 or later. Organizations using S/MIME should ensure all mobile devices are patched and verify encrypted email functionality after updating.
iOS 15.2 and iPadOS 15.2
- Back up your device data before upgrading
- Ensure your device has sufficient battery or is connected to power
- Go to Settings > General > Software Update
- Download and install iOS 15.2 or iPadOS 15.2
- Verify the update was successful by checking Settings > General > About > iOS Version
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation3.0 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 $2,272.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-30997 — 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-2021-30997 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
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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