CVE-2023-48733
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.
02 Description
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.
03 Exploitation and scoring
- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 0.25% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 17.0% of scored records. A rank, not a probability.
- NVD base score
- 6.7 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2024-02-14 21:54Z2 YR AGO
- Last updated
- 2025-05-08 15:18Z1 YR AGO
- Reserved
- 2023-12-05
- Assigning CNA
- canonical
- Record state
- PUBLISHED
- Severity
- Medium (CVSS 6.7)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-1188Initialization of a Resource with an Insecure DefaultBase
- Data version
- 5.1
- Document digest
- 465a94751ac0da744c733d3216924b0b5802efc5d000880307361681c3f6bc19
05 Affected products
06 References
- bugs.launchpad.nethttps://bugs.launchpad.net/ubuntu/+source/edk2/+bug/2040137
- nvd.nist.govhttps://nvd.nist.gov/vuln/detail/CVE-2023-48733
- www.openwall.comhttps://www.openwall.com/lists/oss-security/2024/02/14/4
- bugs.launchpad.nethttps://bugs.launchpad.net/ubuntu/+source/lxd/+bug/2040139
- lists.debian.orghttps://lists.debian.org/debian-lts-announce/2024/06/msg00028.html
07 Fixed in
Debian 12
- edk2 Fixed in 2022.11-6+deb12u1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- edk2 Fixed in 2023.11-7
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- edk2 Fixed in 2023.11-7
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- edk2 Fixed in 0~20191122.bd85bf54-2ubuntu3.5
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- edk2 Fixed in 2022.02-3ubuntu0.22.04.2
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- edk2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 18.04 LTS
- edk2 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.