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CVE-2023-48733· NVD / CVE Program· CNA canonical

An insecure default to allow UEFI Shell in EDK2 was left enabled in Ubuntu's EDK2.

Noroxi assessment

Priority: Monitor (action score 26/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.25% (FIRST EPSS).
  • Someone with local access to the system can trigger it. Administrator privileges are required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Canonical Ltd. Ubuntu EDK II 2023.05-2ubuntu0.1.

Low priority for now. Upgrade to Canonical Ltd. Ubuntu EDK II 2023.05-2ubuntu0.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

An insecure default to allow UEFI Shell in EDK2 was left enabled in Ubuntu's EDK2. This allows an OS-resident attacker to bypass Secure Boot.

MediumCVSS 6.7 · v3.1—No exploit Fix available
Published
Feb 14, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 16th percentile

Report tools

JSON

Action score

26

Monitor

Low priority for now.

CVSS
26 / 40 · 6.7 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · canonical
6.7
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2023-48733

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
canonicallxd
tianocoreedk2
debiandebian linux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • canonical lxd5.0
  • canonical lxd5.21
  • debian debian linux10.0
  • tianocore edk2up to 2023.11-8 inclusive

Versions reported by the vendor

Affected version ranges reported by the assigning authority (canonical). Independent of NVD's CPE analysis and usually ahead of it.

  • Canonical Ltd. Ubuntu EDK II

    • before 2023.05-2ubuntu0.1affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:10edk2before 0~20181115.85588389-3+deb10u40~20181115.85588389-3+deb10u4
Debian:11edk2before 2020.11-2+deb11u22020.11-2+deb11u2
Debian:12edk2before 2022.11-6+deb12u12022.11-6+deb12u1
Debian:13edk2before 2023.11-72023.11-7
openSUSE:Tumbleweedovmfbefore 202308-7.1202308-7.1

Same product

canonical: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-87799Arbitrary file write on LXD host via symlink in migration stream
    39Monitor
  • CVE-2026-85526Path traversal via Btrfs optimized-backup subvolumes[].path enables root file/dir manipulation in LXD
    39Monitor
  • CVE-2026-66897Instance template path traversal allows arbitrary host file write as root
    39Monitor

Published before and after this one in the same product

  • Later →CVE-2023-49721Feb 14, 2024 · An insecure default to allow UEFI Shell in EDK2 was left enabled in LXD.
    26Monitor
  • Later →CVE-2024-6156Dec 5, 2024 · Mark Laing discovered that LXD's PKI mode, until version 5.21.2, could be bypassed if the client's certificate was present in the trust stor
    15Monitor
  • Later →CVE-2024-6219Dec 5, 2024 · Mark Laing discovered in LXD's PKI mode, until version 5.21.1, that a restricted certificate could be added to the trust store with its rest
    15Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Canonical Ltd. Ubuntu EDK II2023.05-2ubuntu0.1Vendor (CNA)
debian:edk22022.11-6+deb12u1 · Debian:12Package registry (OSV)
opensuse:ovmf202308-7.1 · openSUSE:TumbleweedPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • Administrator privileges are required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
High
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-1188 · Initialization of a Resource with an Insecure Default

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records