Cyber Resilience

CVE-2025-15468

Memory Safety in Openssl 3.3.0 – 3.3.6

Published
27 January 2026
Modified
02 February 2026
Patch / advisory
CVSS Score v3.1 5.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0075 52th percentile
Risk Priority 47 floored blend · peak EPSS

Summary

CVE-2025-15468 is a medium-severity NULL Pointer Dereference (CWE-476) vulnerability in Openssl Openssl. Its CVSS base score is 5.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked in the top 48% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Issue summary: If an application using the SSL_CIPHER_find() function in a QUIC protocol client or server receives an unknown cipher suite from the peer, a NULL dereference occurs. Impact summary: A NULL pointer dereference leads to abnormal termination of the…

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running process causing Denial of Service. Some applications call SSL_CIPHER_find() from the client_hello_cb callback on the cipher ID received from the peer. If this is done with an SSL object implementing the QUIC protocol, NULL pointer dereference will happen if the examined cipher ID is unknown or unsupported. As it is not very common to call this function in applications using the QUIC protocol and the worst outcome is Denial of Service, the issue was assessed as Low severity. The vulnerable code was introduced in the 3.2 version with the addition of the QUIC protocol support. The FIPS modules in 3.6, 3.5, 3.4 and 3.3 are not affected by this issue, as the QUIC implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4 and 3.3 are vulnerable to this issue. OpenSSL 3.0, 1.1.1 and 1.0.2 are not affected by this issue.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-28388Same product: Openssl Openssl
CVE-2023-0217Same product: Openssl Openssl
CVE-2026-42765Same product: Openssl Openssl
CVE-2026-28389Same product: Openssl Openssl
CVE-2026-42767Same product: Openssl Openssl
CVE-2025-69421Same product: Openssl Openssl
CVE-2024-0727Same product: Openssl Openssl
CVE-2026-28390Same product: Openssl Openssl
CVE-2026-42764Same product: Openssl Openssl
CVE-2026-42766Same product: Openssl Openssl

Affected Assets

openssl
openssl
3.3.0 — 3.3.6 · 3.4.0 — 3.4.4 · 3.5.0 — 3.5.5

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (including static analysis) directly finds null-dereference bugs before deployment.

Documented development standards and tools can enforce null-safety rules and safe pointer usage.

Engineering principles can mandate defensive coding such as explicit null checks before dereference.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References