Out-of-bounds Read in Curl

CVE-2024-6874

libcurl's URL API function [curl_url_get()](https://curl.se/libcurl/c/curl_url_get.html) offers punycode conversions, to and from IDN. Asking to convert a name that is exactly 256 bytes, libcurl ends up reading outside of a stack based buffer when built to use the *macidn* IDN backend. The conversion function then fills up the provided buffer exactly - but does not null terminate the string. This flaw can lead to stack contents accidently getting returned as part of the converted string.

Vulnerability class: Buffer Overflow

EPSS: 0.008 (52.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2024-6874?
CVE-2024-6874 is a medium-severity vulnerability in Curl, classified under Out-of-bounds Read. CVSS score: 4.3/10. Published 2024-07-24.
How severe is CVE-2024-6874?
Medium severity. CVSS v3 base score is 4.3 out of 10.
Is CVE-2024-6874 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.