How severe is CVE-2024-56521?

CVE-2024-56521 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2024-56521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-56521?

CVE-2024-56521 affects Tcpdf Project Tcpdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-56521?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2024-56521 have an EU (EUVD) identifier?

Yes. CVE-2024-56521 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3571.

When was CVE-2024-56521 published?

CVE-2024-56521 was published on 2024-12-27 and last updated on 2026-06-17.

CVE-2024-56521

CVE-2024-56521 is a critical-severity vulnerability in Tcpdf Project Tcpdf with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-3571
Weakness: CWE-295
Affected product: Tcpdf Project Tcpdf
Published: 2024-12-27
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is 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.
How severe is CVE-2024-56521?: CVE-2024-56521 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-56521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-56521?: CVE-2024-56521 affects Tcpdf Project Tcpdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-56521?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2024-56521 have an EU (EUVD) identifier?: Yes. CVE-2024-56521 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3571.
When was CVE-2024-56521 published?: CVE-2024-56521 was published on 2024-12-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:tcpdf_project:tcpdf:*:*:*:*:*:*:*:*

More vulnerabilities in Tcpdf Project Tcpdf

CVE-2024-56527 — High (CVSS 7.5): An issue was discovered in TCPDF before 6.8.0. The Error function lacks an htmlspecialchars call for the error message.
CVE-2024-56522 — High (CVSS 7.5): An issue was discovered in TCPDF before 6.8.0. unserializeTCPDFtag uses != (aka loose comparison) and does not use a…
CVE-2024-56519 — High (CVSS 7.5): An issue was discovered in TCPDF before 6.8.0. setSVGStyles does not sanitize the SVG font-family attribute.
CVE-2024-22641 — High (CVSS 7.5): TCPDF version 6.6.5 and before is vulnerable to ReDoS (Regular Expression Denial of Service) if parsing an untrusted…
CVE-2024-22640 — High (CVSS 7.5): TCPDF version <=6.6.5 is vulnerable to ReDoS (Regular Expression Denial of Service) if parsing an untrusted HTML page…
CVE-2017-6100 — High (CVSS 7.5): tcpdf before 6.2.0 uploads files from the server generating PDF-files to an external FTP.

All CVEs affecting Tcpdf Project Tcpdf →

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