Red Hat Enterprise Linux 7: Origin Validation Error
CVE-2023-40547 is a high-severity origin validation error vulnerability in Red Hat Enterprise Linux 7 from Red Hat, with a CVSS 3.1 base score of 8.3 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 5.42% chance of exploitation within 30 days, which is in the top 7.17% of all scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Shim to 15.8 or a later version.
- Read the advisory on access.redhat.com for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.3 | High | CNA (redhat.com) |
| CVSS 3.1 | 8.3 | High | NVD |
Official description
A remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP request, leading to a completely controlled out-of-bounds write primitive and complete system compromise. This flaw is only exploitable during the early boot phase, an attacker needs to perform a Man-in-the-Middle or compromise the boot server to be able to exploit this vulnerability successfully.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Origin Validation Error
The product does not properly verify that the source of data or communication is valid.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other references
- access.redhat.com/errata/RHSA-2024:1834
- access.redhat.com/errata/RHSA-2024:1835
- access.redhat.com/errata/RHSA-2024:1873
- access.redhat.com/errata/RHSA-2024:1876
- access.redhat.com/errata/RHSA-2024:1883
- access.redhat.com/errata/RHSA-2024:1902
- access.redhat.com/errata/RHSA-2024:1903
- access.redhat.com/errata/RHSA-2024:1959
- access.redhat.com/errata/RHSA-2024:2086
- openwall.com/lists/oss-security/2024/01/26/1
- lists.debian.org/debian-lts-announce/2024/05/msg00009.html
Other vulnerabilities in Red Hat Enterprise Linux 7
- 7.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.9 High severity
- 7.3 High severity
- 7.5 High severity
Recent Origin Validation Error vulnerabilities
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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