What is CVE-2026-6429?

CVE-2026-6429 is a medium-severity vulnerability in Curl, classified under Information Disclosure. CVSS score: 5.3/10. Published 2026-05-13.

How severe is CVE-2026-6429?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Information disclosure in Curl

CVE-2026-6429

When asked to both use a `.netrc` file for credentials and to follow HTTP redirects, libcurl could leak the password used for the first host to the followed-to host under certain circumstances.

Vulnerability class: Information Disclosure

Published 2026-05-13 · last modified 2026-09-15.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (41.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: -0.000

Affected products

Curl — versions 8.19.0, 8.18.0, 8.17.0
Haxx Curl

Weakness classification (CWE)

CWE-200 — Information Disclosure

References

2499f714-1537-4658-8207-48ae4bb9eae9 (Product)
2499f714-1537-4658-8207-48ae4bb9eae9 (Patch, Vendor Advisory)
2499f714-1537-4658-8207-48ae4bb9eae9 (Exploit, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2026-6429?: CVE-2026-6429 is a medium-severity vulnerability in Curl, classified under Information Disclosure. CVSS score: 5.3/10. Published 2026-05-13.
How severe is CVE-2026-6429?: Medium severity. CVSS v3 base score is 5.3 out of 10.