CVE-2023-40550
published 2024-01-29CVE-2023-40550: An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot…
PriorityP424medium5.5CVSS 3.1
AVLACLPRLUINSUCHINAN
EPSS
0.40%
32.8th percentile
An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.
Affected
24 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | shim | < shim 15.8-1~deb12u1 (bookworm) | shim 15.8-1~deb12u1 (bookworm) |
| fedoraproject | fedora | — | — |
| msrc | azl3_shim-unsigned-aarch64_15.4-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_shim-unsigned-aarch64_15.8-5_on_azure_linux_3.0 | — | — |
| msrc | azl3_shim-unsigned-x64_15.4-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_shim-unsigned-x64_15.8-5_on_azure_linux_3.0 | — | — |
| msrc | azl3_shim_15.4-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_shim_15.8-5_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_shim-unsigned-aarch64_15-5_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_shim-unsigned-x64_15.4-2_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_shim-unsigned-x64_15.8-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_shim_15.4-2_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_shim_15.8-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | shim | < 15.8 | 15.8 |
| redhat | shim | >= 0 < 15.8-1~deb11u1 | 15.8-1~deb11u1 |
| redhat | shim | >= 0 < 15.8-1~deb12u1 | 15.8-1~deb12u1 |
| redhat | shim | >= 0 < 15.8-1 | 15.8-1 |
| redhat | shim | >= 0 < 15.8-1 | 15.8-1 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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GHSA
GHSA-grx2-83w4-8647: An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information
ghsa_unreviewed·2024-01-29
CVE-2023-40550 [MEDIUM] CWE-125 GHSA-grx2-83w4-8647: An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information
An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.
OSV
CVE-2023-40550: An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information
osv·2024-01-29·CVSS 5.5
CVE-2023-40550 [MEDIUM] CVE-2023-40550: An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information
An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.
Red Hat
shim: Out-of-bound read in verify_buffer_sbat()
vendor_redhat·2024-01-23·CVSS 5.5
CVE-2023-40550 [MEDIUM] CWE-125 shim: Out-of-bound read in verify_buffer_sbat()
shim: Out-of-bound read in verify_buffer_sbat()
An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.
An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.
Microsoft
Shim: out-of-bound read in verify_buffer_sbat()
vendor_msrc·2024-01-09·CVSS 5.5
CVE-2023-40550 [MEDIUM] CWE-125 Shim: out-of-bound read in verify_buffer_sbat()
Shim: out-of-bound read in verify_buffer_sbat()
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
redhat: redhat
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.micro
Debian
CVE-2023-40550: shim - An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT ...
vendor_debian·2023·CVSS 5.5
CVE-2023-40550 [MEDIUM] CVE-2023-40550: shim - An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT ...
An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.
Scope: local
bookworm: resolved (fixed in 15.8-1~deb12u1)
bullseye: resolved (fixed in 15.8-1~deb11u1)
forky: resolved (fixed in 15.8-1)
sid: resolved (fixed in 15.8-1)
trixie: resolved (fixed in 15.8-1)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://access.redhat.com/errata/RHSA-2024:1834https://access.redhat.com/errata/RHSA-2024:1835https://access.redhat.com/errata/RHSA-2024:1873https://access.redhat.com/errata/RHSA-2024:1876https://access.redhat.com/errata/RHSA-2024:1883https://access.redhat.com/errata/RHSA-2024:1902https://access.redhat.com/errata/RHSA-2024:1903https://access.redhat.com/errata/RHSA-2024:1959https://access.redhat.com/errata/RHSA-2024:2086https://access.redhat.com/security/cve/CVE-2023-40550https://bugzilla.redhat.com/show_bug.cgi?id=2259915https://access.redhat.com/errata/RHSA-2024:1834https://access.redhat.com/errata/RHSA-2024:1835https://access.redhat.com/errata/RHSA-2024:1873https://access.redhat.com/errata/RHSA-2024:1876https://access.redhat.com/errata/RHSA-2024:1883https://access.redhat.com/errata/RHSA-2024:1902https://access.redhat.com/errata/RHSA-2024:1903https://access.redhat.com/errata/RHSA-2024:1959https://access.redhat.com/errata/RHSA-2024:2086https://access.redhat.com/security/cve/CVE-2023-40550https://bugzilla.redhat.com/show_bug.cgi?id=2259915https://lists.debian.org/debian-lts-announce/2024/05/msg00009.html
2024-01-29
Published