How severe is CVE-2024-56522?

CVE-2024-56522 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2024-56522 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-56522?

CVE-2024-56522 affects Tcpdf Project Tcpdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-56522?

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

Does CVE-2024-56522 have an EU (EUVD) identifier?

Yes. CVE-2024-56522 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3618.

When was CVE-2024-56522 published?

CVE-2024-56522 was published on 2024-12-27 and last updated on 2026-06-17.

CVE-2024-56522

CVE-2024-56522 is a high-severity vulnerability in Tcpdf Project Tcpdf with a CVSS 3.x base score of 7.5. 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-843.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-3618
Weakness: CWE-843
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. unserializeTCPDFtag uses != (aka loose comparison) and does not use a constant-time function to compare TCPDF tag hashes.

Frequently asked questions

What is CVE-2024-56522?: An issue was discovered in TCPDF before 6.8.0. unserializeTCPDFtag uses != (aka loose comparison) and does not use a constant-time function to compare TCPDF tag hashes.
How severe is CVE-2024-56522?: CVE-2024-56522 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2024-56522 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-56522?: CVE-2024-56522 affects Tcpdf Project Tcpdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-56522?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-56522 have an EU (EUVD) identifier?: Yes. CVE-2024-56522 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3618.
When was CVE-2024-56522 published?: CVE-2024-56522 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-2024-56521 — Critical (CVSS 9.8): An issue was discovered in TCPDF before 6.8.0. If libcurl is used, CURLOPT_SSL_VERIFYHOST and CURLOPT_SSL_VERIFYPEER…
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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…
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