Cyber Resilience

CVE-2026-3497

Memory Safety in Canonical Ubuntu Linux 20.04 … 25.10

Memory Safety
Published
12 March 2026
Modified
15 July 2026
CVSS Score v4 6.9
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.022 81th percentile
Risk Priority 45 floored blend · peak EPSS

Summary

CVE-2026-3497 is a medium-severity Use of Uninitialized Resource (CWE-908) vulnerability in Canonical Ubuntu Linux. Its CVSS base score is 6.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Credential Dumping (T1003); ranked in the top 19% 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.

EU & UK References

Vulnerability Data

Vulnerability in the OpenSSH GSSAPI delta included in various Linux distributions. This vulnerability affects the GSSAPI patches added by various Linux distributions and does not affect the OpenSSH upstream project itself. The usage of sshpkt_disconnect() on an error, which does…

more

not terminate the process, allows an attacker to send an unexpected GSSAPI message type during the GSSAPI key exchange to the server, which will call the underlying function and continue the execution of the program without setting the related connection variables. As the variables are not initialized to NULL the code later accesses those uninitialized variables, accessing random memory, which could lead to undefined behavior. The recommended workaround is to use ssh_packet_disconnect() instead, which does terminate the process. The impact of the vulnerability depends heavily on the compiler flag hardening configuration.

CWE(s)
CWE-908CWE-824

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-26466Same product: Canonical Ubuntu Linux
CVE-2026-55654Same product: Openbsd Openssh
CVE-2023-42753Same product: Debian Debian Linux
CVE-2023-42755Same product: Debian Debian Linux
CVE-2025-2173Shared CWE-824, CWE-908
CVE-2026-45736Shared CWE-824, CWE-908
CVE-2026-6749Shared CWE-824, CWE-908
CVE-2025-37995Same product: Debian Debian Linux
CVE-2023-40283Same product: Canonical Ubuntu Linux
CVE-2023-3777Same product: Canonical Ubuntu Linux

Affected Assets

canonical
ubuntu linux
20.04, 22.04, 24.04, 25.10
openbsd
openssh
all versions
debian
debian linux
11.0
redhat
enterprise linux
10.0, 8.0, 9.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation (including static analysis) can find uses of uninitialized resources after they are coded.

SA-15 Development Process, Standards, and Tools partial match

Requiring documented development standards and tools can mandate initialization checks and safe patterns that stop the weakness from being introduced.

SA-8 Security and Privacy Engineering Principles partial match

Engineering principles can require explicit resource initialization before use, structurally avoiding uninitialized access.

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 activities such as static analysis and code review directly prevent use of uninitialized resources while also addressing many other weaknesses.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance can detect uninitialized resource usage through dynamic analysis and fuzzing.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates initialization checks and static analysis that can catch uninitialized resource use.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify mandatory initialization of variables and resources before use.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure system architecture and engineering principles include defensive coding practices that prevent use of uninitialized memory or objects.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly require explicit initialization of all variables and resources, substantially mitigating CWE-908.

References