What is CVE-2018-1000168?

nghttp2 version >= 1.10.0 and nghttp2 = 1.31.1.

How severe is CVE-2018-1000168?

CVE-2018-1000168 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-2018-1000168 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 11% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1000168?

CVE-2018-1000168 primarily affects Nghttp2. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-1000168?

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-2018-1000168 published?

CVE-2018-1000168 was published on 2018-05-08 and last updated on 2026-06-17.

CVE-2018-1000168

CVE-2018-1000168 is a high-severity vulnerability in Nghttp2 with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 11% places it in the 95th percentile, indicating an elevated likelihood of exploitation. 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: 11% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Nghttp2
Published: 2018-05-08
Last modified: 2026-06-17

Description

nghttp2 version >= 1.10.0 and nghttp2 <= v1.31.0 contains an Improper Input Validation CWE-20 vulnerability in ALTSVC frame handling that can result in segmentation fault leading to denial of service. This attack appears to be exploitable via network client. This vulnerability appears to have been fixed in >= 1.31.1.

Frequently asked questions

What is CVE-2018-1000168?: nghttp2 version >= 1.10.0 and nghttp2 <= v1.31.0 contains an Improper Input Validation CWE-20 vulnerability in ALTSVC frame handling that can result in segmentation fault leading to denial of service. This attack appears to be exploitable via network client. This vulnerability appears to have been fixed in >= 1.31.1.
How severe is CVE-2018-1000168?: CVE-2018-1000168 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-2018-1000168 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 11% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1000168?: CVE-2018-1000168 primarily affects Nghttp2. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-1000168?: 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-2018-1000168 published?: CVE-2018-1000168 was published on 2018-05-08 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:nghttp2:nghttp2:*:*:*:*:*:*:*:*
cpe:2.3:a:nodejs:node.js:*:*:*:*:-:*:*:*
cpe:2.3:a:nodejs:node.js:*:*:*:*:lts:*:*:*
cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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