CVE-2024-6874: libcurl Out-of-bounds Read

Description

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.

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CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

Affected Products

Vendor	Product	Versions
haxx	libcurl	All

References

Advisories & Patches

https://curl.se/docs/CVE-2024-6874.html https://curl.se/docs/CVE-2024-6874.json https://curl.se/docs/CVE-2024-6874.html https://curl.se/docs/CVE-2024-6874.json

Exploits

https://hackerone.com/reports/2604391 https://hackerone.com/reports/2604391

Other References

http://www.openwall.com/lists/oss-security/2024/07/24/2 http://www.openwall.com/lists/oss-security/2024/07/24/2 https://security.netapp.com/advisory/ntap-20240822-0004/

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2024-6874? +

CVE-2024-6874 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-6874? +

CVE-2024-6874 affects products from haxx, specifically: libcurl. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-6874? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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