How severe is CVE-2017-5223?

CVE-2017-5223 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2017-5223 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-5223?

CVE-2017-5223 affects Phpmailer Project Phpmailer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-5223?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-5223 published?

CVE-2017-5223 was published on 2017-01-16 and last updated on 2026-06-17.

CVE-2017-5223

CVE-2017-5223 is a medium-severity vulnerability in Phpmailer Project Phpmailer with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Phpmailer Project Phpmailer
Published: 2017-01-16
Last modified: 2026-06-17

Description

An issue was discovered in PHPMailer before 5.2.22. PHPMailer's msgHTML method applies transformations to an HTML document to make it usable as an email message body. One of the transformations is to convert relative image URLs into attachments using a script-provided base directory. If no base directory is provided, it resolves to /, meaning that relative image URLs get treated as absolute local file paths and added as attachments. To form a remote vulnerability, the msgHTML method must be called, passed an unfiltered, user-supplied HTML document, and must not set a base directory.

Frequently asked questions

What is CVE-2017-5223?: An issue was discovered in PHPMailer before 5.2.22. PHPMailer's msgHTML method applies transformations to an HTML document to make it usable as an email message body. One of the transformations is to convert relative image URLs into attachments using a script-provided base directory. If no base directory is provided, it resolves to /, meaning that relative image URLs get treated as absolute local file paths and added as attachments. To form a remote vulnerability, the msgHTML method must be called, passed an unfiltered, user-supplied HTML document, and must not set a base directory.
How severe is CVE-2017-5223?: CVE-2017-5223 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2017-5223 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-5223?: CVE-2017-5223 affects Phpmailer Project Phpmailer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-5223?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-5223 published?: CVE-2017-5223 was published on 2017-01-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:phpmailer_project:phpmailer:*:*:*:*:*:*:*:*

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