How severe is CVE-2018-1000121?

CVE-2018-1000121 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-2018-1000121 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1000121?

CVE-2018-1000121 primarily affects Haxx Curl. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-1000121?

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-2018-1000121 published?

CVE-2018-1000121 was published on 2018-03-14 and last updated on 2026-06-17.

CVE-2018-1000121

CVE-2018-1000121 is a high-severity vulnerability in Haxx Curl 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: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Haxx Curl
Published: 2018-03-14
Last modified: 2026-06-17

Description

A NULL pointer dereference exists in curl 7.21.0 to and including curl 7.58.0 in the LDAP code that allows an attacker to cause a denial of service

Frequently asked questions

What is CVE-2018-1000121?: A NULL pointer dereference exists in curl 7.21.0 to and including curl 7.58.0 in the LDAP code that allows an attacker to cause a denial of service
How severe is CVE-2018-1000121?: CVE-2018-1000121 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-2018-1000121 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1000121?: CVE-2018-1000121 primarily affects Haxx Curl. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-1000121?: 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-2018-1000121 published?: CVE-2018-1000121 was published on 2018-03-14 and last updated on 2026-06-17.

References

Affected products (17)

cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*
cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:communications_webrtc_session_controller:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:enterprise_manager_ops_center:12.2.2:*:*:*:*:*:*:*
cpe:2.3:a:oracle:enterprise_manager_ops_center:12.3.3:*:*:*:*:*:*:*
cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.55:*:*:*:*:*:*:*
cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.56:*:*:*:*:*:*:*
cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.57:*:*:*:*:*:*:*

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