X.org Server xkb.c _GetCountedString buffer overflow
A vulnerability classified as critical was found in X.org Server. Affected by this vulnerability is the function _GetCountedString of the file xkb/xkb.c. The manipulation leads to buffer overflow. It is recommended to apply a patch to fix this issue. The associated identifier of this vulnerability is VDB-211051.
- BDU:2023-07830
- ALSA-2023:2248
- ALSA-2023:2249
- ALSA-2023:2805
- ALSA-2023:2806
- DLA-3185-1
- DSA-5278-1
- openSUSE-SU-2024:12427-1
- openSUSE-SU-2024:12428-1
- RHSA-2022:8491
- RHSA-2023:2248
- RHSA-2023:2249
- RHSA-2023:2805
- RHSA-2023:2806
- SUSE-SU-2022:3840-1
- SUSE-SU-2022:3841-1
- SUSE-SU-2022:3850-1
- SUSE-SU-2022:3856-1
- SUSE-SU-2022:3857-1
- SUSE-SU-2022:3862-1
- Published
- Oct 17, 2022
- Updated
- Jun 17, 2026
- EPSS
- 1.6% · 75th percentile
- CWE
- CWE-119
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Report tools
Action score
35
Monitor
Low priority for now.
- CVSS
- 35 / 40 · 8.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.6%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 8.8
- CNA · VulDB
- 5.5
- 3.3 point gap
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| x.org | x server | cpe:2.3:a:x.org:x_server |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- debian debian linux10.0
- debian debian linux11.0
- fedoraproject fedora35
- fedoraproject fedora36
- fedoraproject fedora37
- x.org x serverbefore 21.1.6
Versions reported by the vendor
Affected version ranges reported by the assigning authority (VulDB). Independent of NVD's CPE analysis and usually ahead of it.
X.org Server
- n/aaffected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | xorg-x11-server-common | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-devel | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-source | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-Xdmx | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-Xephyr | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-Xnest | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-Xorg | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-Xvfb | before 1.20.11-15.el8 | 1.20.11-15.el8 |
| AlmaLinux:8 | xorg-x11-server-Xwayland | before 21.1.3-10.el8 | 21.1.3-10.el8 |
| AlmaLinux:9 | xorg-x11-server-common | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-devel | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-source | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-Xdmx | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-Xephyr | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-Xnest | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-Xorg | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-Xvfb | before 1.20.11-17.el9 | 1.20.11-17.el9 |
| AlmaLinux:9 | xorg-x11-server-Xwayland | before 21.1.3-7.el9 | 21.1.3-7.el9 |
| Debian:10 | xorg-server | before 2:1.20.4-1+deb10u6 | 2:1.20.4-1+deb10u6 |
| Debian:11 | xorg-server | before 2:1.20.11-1+deb11u3 | 2:1.20.11-1+deb11u3 |
| Debian:12 | xorg-server | before 2:21.1.4-3 | 2:21.1.4-3 |
| Debian:12 | xwayland | before 2:22.1.5-1 | 2:22.1.5-1 |
| openSUSE:Tumbleweed | xorg-x11-server | before 21.1.4-2.1 | 21.1.4-2.1 |
| openSUSE:Tumbleweed | xwayland | before 22.1.3-2.1 | 22.1.3-2.1 |
+60
Same product
x.org: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-6816Xorg-x11-server: heap buffer overflow in devicefocusevent and procxiquerypointer40Plan
- CVE-2007-6427The XInput extension in X.Org Xserver before 1.4.1 allows context-dependent attackers to execute arbitrary code via requests related to byte38Monitor
- CVE-2026-56000xorg-x11-server / xwayland GLX contextTags Use-After-Free in CommonMakeCurrent()36Monitor
- CVE-2026-34002Xorg: xwayland: x.org x server: information disclosure or denial of service via out-of-bounds read in xkb modifier map handling36Monitor
- CVE-2026-34000Xwayland: xorg: x.org x server: information disclosure and denial of service via out-of-bounds read in xkb geometry processing.36Monitor
- CVE-2022-46344A vulnerability was found in X.Org.36Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| almalinux:xorg-x11-server-common | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-devel | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-source | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-Xdmx | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-Xephyr | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-Xnest | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-Xorg | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-Xvfb | 1.20.11-17.el9 · AlmaLinux:9 | Package registry (OSV) |
| almalinux:xorg-x11-server-Xwayland | 21.1.3-7.el9 · AlmaLinux:9 | Package registry (OSV) |
| debian:xorg-server | 2:21.1.4-3 · Debian:12 | Package registry (OSV) |
| debian:xwayland | 2:22.1.5-1 · Debian:12 | Package registry (OSV) |
| opensuse:xorg-x11-server | 1.20.3-150200.22.5.58.1 · openSUSE:Leap 15.3 | Package registry (OSV) |
| opensuse:xwayland | 21.1.4-150400.3.3.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| red hat:xorg-x11-server | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-common | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-debuginfo | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-devel | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-source | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-Xdmx | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-Xdmx-debuginfo | 0:1.20.11-17.el9 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:xorg-x11-server-Xephyr | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-Xnest | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-Xorg | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-Xvfb | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:xorg-x11-server-Xwayland | 0:1.20.4-19.el7_9 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| suse:xorg-x11-server | 1.20.3-150200.22.5.58.1 · SUSE:Linux Enterprise Module for Basesystem 15 SP3 | Package registry (OSV) |
| suse:xorg-x11-server | 7.6_1.18.3-76.52.1 · SUSE:Linux Enterprise Server 12 SP2-BCL | Package registry (OSV) |
| suse:xwayland | 21.1.4-150400.3.3.1 · SUSE:Linux Enterprise Workstation Extension 15 SP4 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory BufferCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Overflow BuffersCAPEC-100likelihood: High · Very High
- Buffer ManipulationCAPEC-123likelihood: High · Very High
- Client-side Injection-induced Buffer OverflowCAPEC-14likelihood: Medium · High
- Filter Failure through Buffer OverflowCAPEC-24likelihood: High · High
- MIME ConversionCAPEC-42likelihood: High · High
- Overflow Binary Resource FileCAPEC-44likelihood: High · Very High
- Buffer Overflow via Symbolic LinksCAPEC-45likelihood: High · High
ATT&CK techniques
—
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- cgit.freedesktop.org/xorg/xserver/commit/?id=11beef0b7f1ed290348e45618e5fa0d2bffcb72e
- lists.debian.org/debian-lts-announce/2022/11/msg00012.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3QTPFVGYTOY4EWTJEBH3YGDTTU57FZAK/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IOEDFBYPSE3EMVHTEFCVEJD2R2Y5F2A5/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OXZZ6JBDBVBYPDI6DUTY6N36GNW37YHK/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X7W3NXSYK4P3XCZQBI3U6UWP4DPZIMRZ/
- security.gentoo.org/glsa/202305-30
- vuldb.com/?id.211051
- www.debian.org/security/2022/dsa-5278
Vendor advisories and official records. Exploit/PoC links are deliberately left out.