How severe is CVE-2020-13111?

CVE-2020-13111 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-2020-13111 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-13111?

CVE-2020-13111 affects Naviserver Project Naviserver. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-13111?

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-2020-13111 published?

CVE-2020-13111 was published on 2020-05-16 and last updated on 2026-06-17.

CVE-2020-13111

CVE-2020-13111 is a high-severity vulnerability in Naviserver Project Naviserver 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Naviserver Project Naviserver
Published: 2020-05-16
Last modified: 2026-06-17

Description

NaviServer 4.99.4 to 4.99.19 allows denial of service due to the nsd/driver.c ChunkedDecode function not properly validating the length of a chunk. A remote attacker can craft a chunked-transfer request that will result in a negative value being passed to memmove via the size parameter, causing the process to crash.

Frequently asked questions

What is CVE-2020-13111?: NaviServer 4.99.4 to 4.99.19 allows denial of service due to the nsd/driver.c ChunkedDecode function not properly validating the length of a chunk. A remote attacker can craft a chunked-transfer request that will result in a negative value being passed to memmove via the size parameter, causing the process to crash.
How severe is CVE-2020-13111?: CVE-2020-13111 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-2020-13111 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-13111?: CVE-2020-13111 affects Naviserver Project Naviserver. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-13111?: 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-2020-13111 published?: CVE-2020-13111 was published on 2020-05-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:naviserver_project:naviserver:*:*:*:*:*:*:*:*

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