What is CVE-2024-56521?

CVE-2024-56521 is a critical-severity vulnerability in Tcpdf Project, classified under Improper Certificate Validation. CVSS score: 9.8/10. Published 2024-12-27.

How severe is CVE-2024-56521?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Tcpdf Project

CVE-2024-56521

An issue was discovered in TCPDF before 6.8.0. If libcurl is used, CURLOPT_SSL_VERIFYHOST and CURLOPT_SSL_VERIFYPEER are set unsafely.

Vulnerability class: Improper Certificate Validation

Published 2024-12-27 · last modified 2026-06-17.

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.

EPSS exploit prediction

EPSS: 0.008 (54.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Tcpdf Project
Tecnick Tcpdf — versions 0

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

tcpdf.org (Product)
github.com/tecnickcom/TCPDF/compare/6.7.8...6.8.0 (Patch)
github.com/tecnickcom/TCPDF/commit/aab43ab0a824e956276141a28a24c7c0be20f554 (Product)

Frequently asked questions

What is CVE-2024-56521?: CVE-2024-56521 is a critical-severity vulnerability in Tcpdf Project, classified under Improper Certificate Validation. CVSS score: 9.8/10. Published 2024-12-27.
How severe is CVE-2024-56521?: Critical severity. CVSS v3 base score is 9.8 out of 10.