Cyber Resilience

CVE-2023-40476

Memory Safety in Gstreamer ≤ 1.22.6

Published
03 May 2024
Modified
17 March 2026
Patch / advisory
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.020 79th percentile
Risk Priority 73 floored blend · peak EPSS

Summary

CVE-2023-40476 is a high-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Gstreamer Gstreamer. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 21% 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 SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

GStreamer contains a stack-based buffer overflow vulnerability in its H265 video parser that permits remote code execution. The flaw, tracked as CVE-2023-40476 and originally ZDI-CAN-21768, arises from insufficient validation of the length of attacker-supplied data before it is copied into a fixed-size stack buffer during parsing of H265 encoded files. Affected installations include multiple versions of the GStreamer multimedia framework, which is widely used by applications that process untrusted media.

An unauthenticated remote attacker can trigger the issue by supplying a malicious H265 file or stream to any application that uses the vulnerable GStreamer library. Successful exploitation grants arbitrary code execution in the context of the process that invokes the parser, with a CVSS 3.1 score of 8.8 reflecting network attack vector, low complexity, and no required privileges beyond user interaction with the media.

Public advisories published by the GStreamer project and Zero Day Initiative, along with downstream notices such as the Debian LTS announcement, direct users to updated packages that contain the fix for the parsing routine.

EPSS for the vulnerability rose from lower values to a peak of 0.1060 before receding to its current score of 0.0622, indicating measurable post-disclosure exploitation interest.

EU & UK References

Vulnerability Data

GStreamer H265 Parsing Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer. Interaction with this library is required to exploit this vulnerability but attack vectors may vary depending…

more

on the implementation. The specific flaw exists within the parsing of H265 encoded video files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. . Was ZDI-CAN-21768.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
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.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-47806Same product: Gstreamer Gstreamer
CVE-2026-3081Same product: Gstreamer Gstreamer
CVE-2023-50186Same product: Gstreamer Gstreamer
CVE-2024-47607Same product: Gstreamer Gstreamer
CVE-2024-0444Same product: Gstreamer Gstreamer
CVE-2025-6663Same product: Gstreamer Gstreamer
CVE-2024-47538Same product: Gstreamer Gstreamer
CVE-2024-47834Same product: Gstreamer Gstreamer
CVE-2024-47546Same product: Gstreamer Gstreamer
CVE-2023-37328Same product: Gstreamer Gstreamer

Affected Assets

gstreamer
gstreamer
≤ 1.22.6

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and analysis can discover stack-buffer overflows before deployment.

Input validation directly stops untrusted data from exceeding stack buffer bounds.

Memory-protection mechanisms limit the ability to execute injected code after a stack overflow.

Secure-engineering principles include bounds-checked coding and safe buffer handling that avoid introducing the flaw.

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-development practices directly prevent introduction of stack buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability scanning can discover stack buffer overflows but does not prevent their introduction.

PR.PS-02 partial match
prevents

Patching eliminates known instances of the weakness after discovery.

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 (fuzzing, static analysis) detects stack overflows before release.

prevents

Secure SDLC mandates buffer-safety practices that directly prevent stack overflows.

prevents

Application security requirements can specify buffer-size and input-validation rules.

prevents

Secure architecture principles include memory-safety and least-privilege stack usage.

prevents

Secure coding standards explicitly forbid unsafe buffer handling that causes CWE-121.

none

Change-management gates can enforce security reviews that catch buffer issues.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. prevents CWE-121
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-121

References