How severe is CVE-2020-18703?

CVE-2020-18703 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-18703 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-18703?

CVE-2020-18703 affects Quokka Project Quokka. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-18703?

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

When was CVE-2020-18703 published?

CVE-2020-18703 was published on 2021-08-16 and last updated on 2026-06-17.

CVE-2020-18703

CVE-2020-18703 is a critical-severity vulnerability in Quokka Project Quokka with a CVSS 3.x base score of 9.8. 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-611.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-611
Affected product: Quokka Project Quokka
Published: 2021-08-16
Last modified: 2026-06-17

Description

XML External Entities (XXE) in Quokka v0.4.0 allows remote attackers to execute arbitrary code via the component 'quokka/utils/atom.py'.

Frequently asked questions

What is CVE-2020-18703?: XML External Entities (XXE) in Quokka v0.4.0 allows remote attackers to execute arbitrary code via the component 'quokka/utils/atom.py'.
How severe is CVE-2020-18703?: CVE-2020-18703 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-18703 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-18703?: CVE-2020-18703 affects Quokka Project Quokka. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-18703?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-18703 published?: CVE-2020-18703 was published on 2021-08-16 and last updated on 2026-06-17.

References

https://github.com/rochacbruno/quokka/issues/676

Affected products (1)

cpe:2.3:a:quokka_project:quokka:0.4.0:*:*:*:*:*:*:*

More vulnerabilities in Quokka Project Quokka

CVE-2020-18705 — Critical (CVSS 9.8): XML External Entities (XXE) in Quokka v0.4.0 allows remote attackers to execute arbitrary code via the component…
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