How severe is CVE-2020-11766?

CVE-2020-11766 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-11766 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11766?

CVE-2020-11766 primarily affects Ifax Hylafax. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-11766?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-11766 published?

CVE-2020-11766 was published on 2020-05-19 and last updated on 2026-06-17.

CVE-2020-11766

CVE-2020-11766 is a high-severity vulnerability in Ifax Hylafax with a CVSS 3.x base score of 8.8. 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-78.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Ifax Hylafax
Published: 2020-05-19
Last modified: 2026-06-17

Description

sendfax.php in iFAX AvantFAX before 3.3.6 and HylaFAX Enterprise Web Interface before 0.2.5 allows authenticated Command Injection.

Frequently asked questions

What is CVE-2020-11766?: sendfax.php in iFAX AvantFAX before 3.3.6 and HylaFAX Enterprise Web Interface before 0.2.5 allows authenticated Command Injection.
How severe is CVE-2020-11766?: CVE-2020-11766 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-11766 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11766?: CVE-2020-11766 primarily affects Ifax Hylafax. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-11766?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-11766 published?: CVE-2020-11766 was published on 2020-05-19 and last updated on 2026-06-17.

References

ftp://ftp.ifax.com/security/CVE-2020-11766.html

Affected products (2)

cpe:2.3:a:ifax:hylafax:*:*:*:*:enterprise:*:*:*
cpe:2.3:a:avantfax:avantfax:*:*:*:*:*:*:*:*

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