Red Hat Enterprise Linux 10: Out-of-bounds Read
CVE-2026-34003 is a high-severity out-of-bounds read vulnerability in Red Hat Enterprise Linux 10 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 0.25% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Red Hat Enterprise Linux 10 you run against the affected versions below, and install the vendor's latest release.
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 CNA (redhat.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA (redhat.com) |
| CVSS 3.1 | 7.8 | High | CNA |
Official description
A flaw was found in the X.Org X server's XKB key types request validation. A local attacker could send a specially crafted request to the X server, leading to an out-of-bounds memory access vulnerability. This could result in the disclosure of sensitive information or cause the server to crash, leading to a Denial of Service (DoS). In certain configurations, higher impact outcomes may be possible.
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
Other references
- access.redhat.com/errata/RHSA-2026:10739
- access.redhat.com/errata/RHSA-2026:11352
- access.redhat.com/errata/RHSA-2026:11369
- access.redhat.com/errata/RHSA-2026:11388
- access.redhat.com/errata/RHSA-2026:11656
- access.redhat.com/errata/RHSA-2026:11692
- access.redhat.com/errata/RHSA-2026:13414
- access.redhat.com/errata/RHSA-2026:19125
- access.redhat.com/errata/RHSA-2026:19342
- access.redhat.com/errata/RHSA-2026:19343
- access.redhat.com/errata/RHSA-2026:19344
- access.redhat.com/errata/RHSA-2026:20547
- access.redhat.com/errata/RHSA-2026:20555
- access.redhat.com/errata/RHSA-2026:20557
- access.redhat.com/errata/RHSA-2026:20558
Other vulnerabilities in Red Hat Enterprise Linux 10
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.9 High severity
- 7.3 High severity
- 7.5 High severity
Recent Out-of-bounds Read vulnerabilities
- 9.6 Critical severity
- 8.1 High severity
- 9.1 Critical severity
- 7.8 High severity
- 8.1 High severity
- 7.1 High severity
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