Red Hat Enterprise Linux 6 Extended Lifecycle…: Out-of-bounds Read
CVE-2023-6377 is a high-severity out-of-bounds read vulnerability in Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION from Red Hat, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 1.57% chance of exploitation within 30 days, higher than 76% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update X Server to 21.1.10 or a later version.
- Update Xwayland to 23.2.3 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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- 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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA (redhat.com) |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
A flaw was found in xorg-server. Querying or changing XKB button actions such as moving from a touchpad to a mouse can result in out-of-bounds memory reads and writes. This may allow local privilege escalation or possible remote code execution in cases where X11 forwarding is involved.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
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
Patches and release notes
Other references
- access.redhat.com/errata/RHSA-2024:0006
- access.redhat.com/errata/RHSA-2024:0009
- access.redhat.com/errata/RHSA-2024:0010
- access.redhat.com/errata/RHSA-2024:0014
- access.redhat.com/errata/RHSA-2024:0015
- access.redhat.com/errata/RHSA-2024:0016
- access.redhat.com/errata/RHSA-2024:0017
- access.redhat.com/errata/RHSA-2024:0018
- access.redhat.com/errata/RHSA-2024:0020
- access.redhat.com/errata/RHSA-2024:2169
- access.redhat.com/errata/RHSA-2024:2170
- access.redhat.com/errata/RHSA-2024:2995
- access.redhat.com/errata/RHSA-2024:2996
- access.redhat.com/errata/RHSA-2025:13998
- bugzilla.redhat.com/show_bug.cgi?id=2253291Issue Tracking
Other vulnerabilities in Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION
- 9.8 Critical severity
- 7.5 High severity
- 7.5 High severity
- 8.1 High severity
- 7.8 High severity
- 7.8 High severity
Recent Out-of-bounds Read vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.1 High severity
- 7.1 High severity
- 7.5 High severity
- 7.5 High severity
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