How severe is GHSA-gmc6-fwg3-75m5?

GHSA-gmc6-fwg3-75m5 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-gmc6-fwg3-75m5?

GHSA-gmc6-fwg3-75m5 affects the following packages: MimeKit (NuGet). Ecosystems affected: NuGet.

How do I fix GHSA-gmc6-fwg3-75m5?

Update MimeKit to 4.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gmc6-fwg3-75m5 is resolved across your whole dependency graph.

How do I detect GHSA-gmc6-fwg3-75m5 in my NuGet dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for MimeKit. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-gmc6-fwg3-75m5 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-gmc6-fwg3-75m5?

O3 pinpoints whether GHSA-gmc6-fwg3-75m5 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-gmc6-fwg3-75m5 actively exploited in the wild?

No public exploit code has been indexed for GHSA-gmc6-fwg3-75m5 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was GHSA-gmc6-fwg3-75m5 published, and has it been updated?

GHSA-gmc6-fwg3-75m5 was published on July 11, 2024 and was last updated on November 29, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

.NET NuGet

GHSA-gmc6-fwg3-75m5

HIGH

Mimekit has vulnerable dependency that can lead to denial of service

Published

Jul 11, 2024

Updated

Nov 29, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Blast Radius

1 pkg affected

.NETMimeKit

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.

Description

Summary

Denial of service vulnerability.

Details

See: https://github.com/advisories/GHSA-447r-wph3-92pm and https://github.com/dotnet/announcements/issues/312

PoC

Update System.Security.Cryptography.Pkcs to 8.0.1 so that the transitive dependency with the issue gets updated

Impact

Denial of service vulnerability. Affects MimeKit (>= v3.0.0 and <= v4.7.0) when used to decrypt or verify incoming S/MIME messages as well as importing 3rd-party X.509 certificates for use with encrypting outgoing S/MIME messages.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
.NETNuGet	`MimeKit`	≥ 3.0.0&&< 4.7.1	4.7.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for MimeKit. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update MimeKit to 4.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gmc6-fwg3-75m5 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-gmc6-fwg3-75m5 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-gmc6-fwg3-75m5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Denial of service vulnerability. ### Details See: https://github.com/advisories/GHSA-447r-wph3-92pm and https://github.com/dotnet/announcements/issues/312 ### PoC Update System.Security.Cryptography.Pkcs to 8.0.1 so that the transitive dependency with the issue gets updated ### Impact Denial of service vulnerability. Affects MimeKit (>= v3.0.0 and <= v4.7.0) when used to decrypt or verify incoming S/MIME messages as well as importing 3rd-party X.509 certificates for use with encrypting outgoing S/MIME messages.

O3 Security · Impact-Aware SCA

Is GHSA-gmc6-fwg3-75m5 in your dependencies?

O3 detects GHSA-gmc6-fwg3-75m5 across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works