Use After Free in Haxx Curl

CVE-2018-16840

A heap use-after-free flaw was found in curl versions from 7.59.0 through 7.61.1 in the code related to closing an easy handle. When closing and cleaning up an 'easy' handle in the `Curl_close()` function, the library code first frees a st…

Vulnerability class: Use-After-Free

EPSS: 0.034 (87.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2018-16840?
CVE-2018-16840 is a critical-severity vulnerability in Haxx Curl, classified under Use After Free. CVSS score: 9.8/10. Published 2018-10-31.
How severe is CVE-2018-16840?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2018-16840 known to be exploited?
7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.