How severe is CVE-2020-15689?

CVE-2020-15689 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-15689 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-15689?

CVE-2020-15689 affects Embedthis Appweb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-15689?

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-2020-15689 published?

CVE-2020-15689 was published on 2020-07-13 and last updated on 2026-06-17.

CVE-2020-15689

CVE-2020-15689 is a high-severity vulnerability in Embedthis Appweb with a CVSS 3.x base score of 7.5. 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Embedthis Appweb
Published: 2020-07-13
Last modified: 2026-06-17

Description

Appweb before 7.2.2 and 8.x before 8.1.0, when built with CGI support, mishandles an HTTP request with a Range header that lacks an exact range. This may result in a NULL pointer dereference and cause a denial of service.

Frequently asked questions

What is CVE-2020-15689?: Appweb before 7.2.2 and 8.x before 8.1.0, when built with CGI support, mishandles an HTTP request with a Range header that lacks an exact range. This may result in a NULL pointer dereference and cause a denial of service.
How severe is CVE-2020-15689?: CVE-2020-15689 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-15689 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-15689?: CVE-2020-15689 affects Embedthis Appweb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-15689?: 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-2020-15689 published?: CVE-2020-15689 was published on 2020-07-13 and last updated on 2026-06-17.

References

https://github.com/embedthis/appweb-gpl/issues/2

Affected products (1)

cpe:2.3:a:embedthis:appweb:*:*:*:*:*:*:*:*

More vulnerabilities in Embedthis Appweb

CVE-2018-8715 — High (CVSS 8.1): The Embedthis HTTP library, and Appweb versions before 7.0.3, have a logic flaw related to the authCondition function…
CVE-2021-33254 — High (CVSS 7.5): An issue was discovered in src/http/httpLib.c in EmbedThis Appweb Community Edition 8.2.1, allows attackers to cause a…
CVE-2018-15505 — High (CVSS 7.5): An issue was discovered in Embedthis GoAhead before 4.0.1 and Appweb before 7.0.2. An HTTP POST request with a…
CVE-2018-15504 — High (CVSS 7.5): An issue was discovered in Embedthis GoAhead before 4.0.1 and Appweb before 7.0.2. The server mishandles some HTTP…
CVE-2014-9708 — Medium (CVSS 5.0): Embedthis Appweb before 4.6.6 and 5.x before 5.2.1 allows remote attackers to cause a denial of service (NULL pointer…

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