How severe is CVE-2020-5577?

CVE-2020-5577 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-2020-5577 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5577?

CVE-2020-5577 primarily affects Sixapart Movable Type. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-5577?

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-2020-5577 published?

CVE-2020-5577 was published on 2020-05-14 and last updated on 2026-06-17.

CVE-2020-5577

CVE-2020-5577 is a high-severity vulnerability in Sixapart Movable Type 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-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Sixapart Movable Type
Published: 2020-05-14
Last modified: 2026-06-17

Description

Movable Type series (Movable Type 7 r.4606 (7.2.1) and earlier (Movable Type 7), Movable Type Advanced 7 r.4606 (7.2.1) and earlier (Movable Type Advanced 7), Movable Type for AWS 7 r.4606 (7.2.1) and earlier (Movable Type for AWS 7), Movable Type 6.5.3 and earlier (Movable Type 6.5), Movable Type Advanced 6.5.3 and earlier (Movable Type Advanced 6.5), Movable Type 6.3.11 and earlier (Movable Type 6.3), Movable Type Advanced 6.3.11 and earlier (Movable Type 6.3), Movable Type Premium 1.29 and earlier, and Movable Type Premium Advanced 1.29 and earlier) allow remote authenticated attackers to upload arbitrary files and execute a php script via unspecified vectors.

Frequently asked questions

What is CVE-2020-5577?: Movable Type series (Movable Type 7 r.4606 (7.2.1) and earlier (Movable Type 7), Movable Type Advanced 7 r.4606 (7.2.1) and earlier (Movable Type Advanced 7), Movable Type for AWS 7 r.4606 (7.2.1) and earlier (Movable Type for AWS 7), Movable Type 6.5.3 and earlier (Movable Type 6.5), Movable Type Advanced 6.5.3 and earlier (Movable Type Advanced 6.5), Movable Type 6.3.11 and earlier (Movable Type 6.3), Movable Type Advanced 6.3.11 and earlier (Movable Type 6.3), Movable Type Premium 1.29 and earlier, and Movable Type Premium Advanced 1.29 and earlier) allow remote authenticated attackers to upload arbitrary files and execute a php script via unspecified vectors.
How severe is CVE-2020-5577?: CVE-2020-5577 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-2020-5577 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5577?: CVE-2020-5577 primarily affects Sixapart Movable Type. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-5577?: 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-2020-5577 published?: CVE-2020-5577 was published on 2020-05-14 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:sixapart:movable_type:*:*:*:*:advanced:*:*:*
cpe:2.3:a:sixapart:movable_type:*:*:*:*:premium:*:*:*
cpe:2.3:a:sixapart:movable_type:*:*:*:*:-:*:*:*
cpe:2.3:a:sixapart:movable_type:*:*:*:*:*:aws:*:*

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