Security Resilience

CVE-2023-45236

Info Disclosure in Tianocore Edk2 ≤ 202311

Published
16 January 2024
Modified
04 November 2025
Patch / advisory
CVSS Score v3.1 5.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
EPSS Score 0.0099 62th percentile
Risk Priority 48 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-45236 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Tianocore Edk2. Its CVSS base score is 5.8 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 38% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

EDK2's Network Package is susceptible to a predictable TCP Initial Sequence Number. This vulnerability can be exploited by an attacker to gain unauthorized access and potentially lead to a loss of Confidentiality.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control
Adversaries may obfuscate command and control traffic to make it more difficult to detect.
T1001.002 Steganography Command And Control
Adversaries may use steganographic techniques to hide command and control traffic to make detection efforts more difficult.
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.
T1007 System Service Discovery Discovery
Adversaries may try to gather information about registered local system services.
T1011 Exfiltration Over Other Network Medium Exfiltration
Adversaries may attempt to exfiltrate data over a different network medium than the command and control channel.
T1011.001 Exfiltration Over Bluetooth Exfiltration
Adversaries may attempt to exfiltrate data over Bluetooth rather than the command and control channel.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-45237Same product: Tianocore Edk2
CVE-2023-45233Same product: Tianocore Edk2
CVE-2023-45232Same product: Tianocore Edk2
CVE-2023-45229Same product: Tianocore Edk2
CVE-2023-45231Same product: Tianocore Edk2
CVE-2025-2486Same product: Tianocore Edk2
CVE-2023-45230Same product: Tianocore Edk2
CVE-2023-45234Same product: Tianocore Edk2
CVE-2023-45235Same product: Tianocore Edk2
CVE-2025-7394Shared CWE-200, CWE-338

Affected Assets

tianocore
edk2
≤ 202311

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V7.2.3
  • V11.5.1

Mitigating Controls (NIST 800-53 r5) AI

Access enforcement directly stops unauthorized actors from obtaining sensitive information.

Information flow enforcement structurally prevents sensitive data from reaching unauthorized recipients.

Requiring specific approved cryptography for protection directly mandates use of strong PRNGs instead of weak ones.

Protection of information at rest prevents unauthorized exposure of stored sensitive data.

Transmission confidentiality mechanisms stop exposure of sensitive data on the wire.

Least privilege reduces the set of actors who can reach sensitive information.

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 partial match
blocks

Secure SDLC practices explicitly require cryptographically strong RNG selection and usage in security contexts.

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.

blocks

A.5.10 only requires awareness, a topic-specific acceptable-use policy stating expected behaviours/monitoring, and procedures referencing classification and other controls; per the owner's explicit rule on labelling and similar dependency-style clauses, this does not itself prevent exposure (CWE-200) unless access/DLP/etc. act on it.

blocks

Requiring the return of all physical and electronic assets plus secure deletion of organizational data from personal devices reduces the chance that sensitive information remains accessible to departing personnel.

blocks

A.5.12 only defines and communicates a classification scheme so that protection needs can be understood; per the owner's explicit rule, labeling/classification does not itself prevent exposure and requires other controls (e.g. access enforcement) to act on it.

blocks

By requiring classification labels and metadata on all information assets, the control makes it harder for sensitive data to be inadvertently exposed because downstream systems and users can recognize and enforce handling rules based on those labels.

blocks

Requiring encryption, access controls, and recipient authentication for transfers directly reduces the chance that sensitive data reaches an unauthorized observer.

removes

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` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248563 The OL 8 SSH server must be configured to use strong entropy. blocks CWE-338
RHEL 8 (1 rule)
  • V-230253 RHEL 8 must ensure the SSH server uses strong entropy. blocks CWE-338
Ubuntu 22.04 (1 rule)
  • V-260650 Ubuntu 22.04 LTS must implement NIST FIPS-validated cryptography to protect classified information and for the following: To provision digital signatures, to generate cryptographic hashes, and to protect unclassified information requiring confidentiality and cryptographic protection in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. blocks CWE-338

References