How severe is CVE-2018-16789?

CVE-2018-16789 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-2018-16789 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-16789?

CVE-2018-16789 affects Shellinabox Project Shellinabox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-16789?

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-2018-16789 published?

CVE-2018-16789 was published on 2019-03-21 and last updated on 2026-06-17.

CVE-2018-16789

CVE-2018-16789 is a high-severity vulnerability in Shellinabox Project Shellinabox 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-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Shellinabox Project Shellinabox
Published: 2019-03-21
Last modified: 2026-06-17

Description

libhttp/url.c in shellinabox through 2.20 has an implementation flaw in the HTTP request parsing logic. By sending a crafted multipart/form-data HTTP request, an attacker could exploit this to force shellinaboxd into an infinite loop, exhausting available CPU resources and taking the service down.

Frequently asked questions

What is CVE-2018-16789?: libhttp/url.c in shellinabox through 2.20 has an implementation flaw in the HTTP request parsing logic. By sending a crafted multipart/form-data HTTP request, an attacker could exploit this to force shellinaboxd into an infinite loop, exhausting available CPU resources and taking the service down.
How severe is CVE-2018-16789?: CVE-2018-16789 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-2018-16789 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-16789?: CVE-2018-16789 affects Shellinabox Project Shellinabox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-16789?: 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-2018-16789 published?: CVE-2018-16789 was published on 2019-03-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:shellinabox_project:shellinabox:*:*:*:*:*:*:*:*

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