How severe is CVE-2023-24609?

CVE-2023-24609 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 none, integrity none, and availability high.

Is CVE-2023-24609 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-2023-24609?

CVE-2023-24609 primarily affects Matrixssl. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-24609?

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.

When was CVE-2023-24609 published?

CVE-2023-24609 was published on 2023-12-22 and last updated on 2026-06-17.

CVE-2023-24609

CVE-2023-24609 is a high-severity vulnerability in Matrixssl 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-190.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Matrixssl
Published: 2023-12-22
Last modified: 2026-06-17

Description

Matrix SSL 4.x through 4.6.0 and Rambus TLS Toolkit have a length-subtraction integer overflow for Client Hello Pre-Shared Key extension parsing in the TLS 1.3 server. An attacked device calculates an SHA-2 hash over at least 65 KB (in RAM). With a large number of crafted TLS messages, the CPU becomes heavily loaded. This occurs in tls13VerifyBinder and tls13TranscriptHashUpdate.

Frequently asked questions

What is CVE-2023-24609?: Matrix SSL 4.x through 4.6.0 and Rambus TLS Toolkit have a length-subtraction integer overflow for Client Hello Pre-Shared Key extension parsing in the TLS 1.3 server. An attacked device calculates an SHA-2 hash over at least 65 KB (in RAM). With a large number of crafted TLS messages, the CPU becomes heavily loaded. This occurs in tls13VerifyBinder and tls13TranscriptHashUpdate.
How severe is CVE-2023-24609?: CVE-2023-24609 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 none, integrity none, and availability high.
Is CVE-2023-24609 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-2023-24609?: CVE-2023-24609 primarily affects Matrixssl. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-24609?: 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.
When was CVE-2023-24609 published?: CVE-2023-24609 was published on 2023-12-22 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:matrixssl:matrixssl:*:*:*:*:*:*:*:*
cpe:2.3:a:rambus:tls_toolkit:-:*:*:*:*:*:*:*

More vulnerabilities in Matrixssl

CVE-2019-14431 — Critical (CVSS 9.8): In MatrixSSL 3.8.3 Open through 4.2.1 Open, the DTLS server mishandles incoming network messages leading to a…
CVE-2019-13470 — Critical (CVSS 9.8): MatrixSSL before 4.2.1 has an out-of-bounds read during ASN.1 handling.
CVE-2019-10914 — Critical (CVSS 9.8): pubRsaDecryptSignedElementExt in MatrixSSL 4.0.1 Open, as used in Inside Secure TLS Toolkit, has a stack-based buffer…
CVE-2017-2781 — Critical (CVSS 9.8): An exploitable heap buffer overflow vulnerability exists in the X509 certificate parsing functionality of InsideSecure…
CVE-2017-2780 — Critical (CVSS 9.8): An exploitable heap buffer overflow vulnerability exists in the X509 certificate parsing functionality of InsideSecure…
CVE-2016-6890 — Critical (CVSS 9.8): Heap-based buffer overflow in MatrixSSL before 3.8.6 allows remote attackers to execute arbitrary code via a crafted…

All CVEs affecting Matrixssl →

Other CWE-190 (Integer Overflow or Wraparound) vulnerabilities

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CVE-2015-5108 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
CVE-2015-5097 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
CVE-2013-2555 — Critical (CVSS 10.0): Integer overflow in Adobe Flash Player before 10.3.183.75 and 11.x before 11.7.700.169 on Windows and Mac OS X, before…

Browse all CWE-190 (Integer Overflow or Wraparound) vulnerabilities →