How severe is CVE-2015-8476?

CVE-2015-8476 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2015-8476 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-8476?

CVE-2015-8476 primarily affects Phpmailer Project Phpmailer. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-8476?

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

When was CVE-2015-8476 published?

CVE-2015-8476 was published on 2015-12-16 and last updated on 2026-06-17.

CVE-2015-8476

CVE-2015-8476 is a medium-severity vulnerability in Phpmailer Project Phpmailer with a CVSS 2.0 base score of 5.0. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Phpmailer Project Phpmailer
Published: 2015-12-16
Last modified: 2026-06-17

Description

Multiple CRLF injection vulnerabilities in PHPMailer before 5.2.14 allow attackers to inject arbitrary SMTP commands via CRLF sequences in an (1) email address to the validateAddress function in class.phpmailer.php or (2) SMTP command to the sendCommand function in class.smtp.php, a different vulnerability than CVE-2012-0796.

Frequently asked questions

What is CVE-2015-8476?: Multiple CRLF injection vulnerabilities in PHPMailer before 5.2.14 allow attackers to inject arbitrary SMTP commands via CRLF sequences in an (1) email address to the validateAddress function in class.phpmailer.php or (2) SMTP command to the sendCommand function in class.smtp.php, a different vulnerability than CVE-2012-0796.
How severe is CVE-2015-8476?: CVE-2015-8476 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2015-8476 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-8476?: CVE-2015-8476 primarily affects Phpmailer Project Phpmailer. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-8476?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-8476 published?: CVE-2015-8476 was published on 2015-12-16 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:debian:debian_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:a:phpmailer_project:phpmailer:*:*:*:*:*:*:*:*

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