CVE-2017-12156

CVE-2017-12156 is a medium-severity vulnerability in Moodle with a CVSS 3.x base score of 6.1. 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-79.

Key facts

• Severity: Medium (CVSS 3.x base score 6.1)
• CVSS v2: 4.3
• EPSS exploit prediction: 1% (61st percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-79
• Affected product: Moodle
• Published: 2017-09-18
• Last modified: 2026-06-17

Description

Moodle 3.x has XSS in the contact form on the "non-respondents" page in non-anonymous feedback.

Frequently asked questions

What is CVE-2017-12156?

Moodle 3.x has XSS in the contact form on the "non-respondents" page in non-anonymous feedback.

How severe is CVE-2017-12156?

CVE-2017-12156 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2017-12156 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-12156?

CVE-2017-12156 primarily affects Moodle. In total, 43 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-12156?

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

When was CVE-2017-12156 published?

CVE-2017-12156 was published on 2017-09-18 and last updated on 2026-06-17.

References

• http://www.securityfocus.com/bid/100867
• https://moodle.org/mod/forum/discuss.php?d=358585

Affected products (43)

• cpe:2.3:a:moodle:moodle:3.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.0:beta:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.0:rc3:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.0:rc4:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.6:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.7:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.8:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.9:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.0.10:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.0:beta:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.1:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.2:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.3:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.4:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.5:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.6:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.7:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.1.8:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:beta:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:rc1:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:rc2:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:rc3:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:rc4:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.0:rc5:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.1:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.2:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.3:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.4:*:*:*:*:*:*:*
• cpe:2.3:a:moodle:moodle:3.2.5:*:*:*:*:*:*:*

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