Actively Exploited — CISA KEV
CVE-2018-14634: Linux Kernel High-Severity Vulnerability
Severity: High | CVSS 3.0: 7.8 | Published: 2018-09-25 | KEV Added: 2026-01-26
What is CVE-2018-14634?
An integer overflow flaw was found in the Linux kernel's create_elf_tables() function. An unprivileged local user with access to SUID (or otherwise privileged) binary could use this flaw to escalate their privileges on the system. Kernel versions 2.6.x, 3.10.x and 4.14.x are believed to be vulnerable.
Technical Analysis
Weakness Classification
This vulnerability is classified as CWE-190 — Integer Overflow or Wraparound. An integer arithmetic operation produces a value that exceeds the maximum for its type, wrapping around and leading to unexpected behavior or buffer overflows.
Attack Vector Breakdown
- Attack Vector: Local
- Attack Complexity: Low
- Privileges Required: Low
- User Interaction: None
- Scope: Unchanged
- Confidentiality: High
- Integrity: High
- Availability: High
Impact Analysis
Exploitation requires local access to the target system, such as a local user session or a malicious file opened by a user. The attack complexity is low, meaning exploitation does not depend on specialized conditions or race windows. Successful exploitation can result in full confidentiality breach (complete data disclosure), complete integrity compromise (data modification or code execution), total availability loss (denial of service). An integer arithmetic operation produces a value that exceeds the maximum for its type, wrapping around and leading to unexpected behavior or buffer overflows.
Exploitation Probability (EPSS): 20.6% chance of exploitation in the next 30 days (96th percentile). This is a significantly elevated exploitation probability — prioritize patching.
Exploit Availability
Public exploit code or proof-of-concept is available for CVE-2018-14634. This significantly increases the risk of exploitation, as attackers can use or adapt existing exploit code rather than developing their own. A public exploit reference has been identified. Organizations should treat this as an urgent patching priority.
Is CVE-2018-14634 being exploited?
Yes. CVE-2018-14634 is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, restricted to CVEs with confirmed active exploitation in the wild. CISA added this vulnerability on 2026-01-26. Inclusion in KEV triggers the patching mandate under BOD 22-01 for U.S. federal civilian agencies, with a remediation deadline of 2026-02-16. Additionally, public exploit code is available, which lowers the barrier for attackers.
How to fix CVE-2018-14634
Update the Linux kernel to the patched version via your distribution's package manager (apt, yum, dnf). A reboot is typically required after kernel updates. For environments where rebooting is not immediately possible, check if a livepatch/kpatch is available from your distribution vendor. Check the Linux Kernel CVEs page for the specific patch or update. CISA's Known Exploited Vulnerabilities catalog requires U.S. federal agencies to remediate this vulnerability by the due date shown below under Binding Operational Directive 22-01. Private organizations should treat KEV entries as priority-one patches because active exploitation has been confirmed in the wild.
Related Vulnerabilities
Other actively exploited vulnerabilities affecting Kernel or sharing the same weakness (CWE-190):
- CVE-2022-0492 (High 7.8) [same product] — A vulnerability was found in the Linux kernel’s cgroup_release_agent_write in…
- CVE-2026-31431 (High 7.8) [same product] — In the Linux kernel, the following vulnerability has been resolved: crypto…
- CVE-2021-22555 (Unknown N/A) [same product] — Linux Kernel contains a heap out-of-bounds write vulnerability that could…
- CVE-2025-38352 (High 7.4) [same product] — In the Linux kernel, the following vulnerability has been…
- CVE-2023-0386 (Unknown N/A) [same product] — Linux Kernel contains an improper ownership management vulnerability, where…
Frequently asked questions
Is CVE-2018-14634 critical?
CVE-2018-14634 has a CVSS 3.0 base score of 7.8 — High severity. It should be treated as a priority patch, especially given the active exploitation confirmed by CISA. The availability of public exploit code further increases the urgency.
Is CVE-2018-14634 being actively exploited?
Yes — CISA added CVE-2018-14634 to the Known Exploited Vulnerabilities catalog on 2026-01-26. Inclusion in KEV means CISA has confirmed in-the-wild exploitation. Public exploit code has also been identified, making exploitation accessible to a broader range of threat actors.
How do I patch CVE-2018-14634?
Apply the security update from Linux for Kernel. Federal agencies must remediate by 2026-02-16 under BOD 22-01. Refer to the Linux Kernel CVEs for the official patch.
What type of vulnerability is CVE-2018-14634?
CVE-2018-14634 is classified under CWE-190 (Integer Overflow or Wraparound). An integer arithmetic operation produces a value that exceeds the maximum for its type, wrapping around and leading to unexpected behavior or buffer overflows.
What is the CVSS score for CVE-2018-14634?
CVE-2018-14634 has a CVSS 3.0 base score of 7.8, classifying it as High severity. The attack vector is Local, attack complexity is Low, and non-zero privileges are required.