CVE-2019-19680Network attack vector

Malicious attachment delivery via malformed MIME structure

Published Jan 13, 2020 · Updated Aug 5, 2024

Attachment-scanning bypass in Proofpoint Enterprise Protection allows remote attackers to deliver blocked files via malformed multipart email. Certain malformed MIME structures are handled incorrectly, bypassing attachment extension, MIME-type, virus, and file-blocking checks. The recipient must open the delivered attachment for impact, while spam, reputation, URL, and click-time controls remain unaffected.

CVSS severity8.8
High
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Attachment-scanning bypass in Proofpoint Enterprise Protection allows remote attackers to deliver blocked files via malformed multipart email. Certain malformed MIME structures are handled incorrectly, bypassing attachment extension, MIME-type, virus, and file-blocking checks. The recipient must open the delivered attachment for impact, while spam, reputation, URL, and click-time controls remain unaffected.

The record

CVE
CVE-2019-19680
Published
Jan 13, 2020
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1566.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.9ProofpointCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1566.001Spearphishing Attachment

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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