CVE-2026-18938: Heap-based Buffer Overflow in Red Hat Red Hat Enterprise Linux 10
CVE-2026-18938 is a heap-based buffer overflow vulnerability in the p11-kit component of Red Hat Enterprise Linux 10. It arises from an integer overflow that causes miscalculation of memory allocation for nested attributes, leading to heap out-of-bounds writes. This flaw can be exploited locally or by an attacker with access to a reachable RPC channel to crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). The vulnerability is only exploitable on 32-bit systems. No official fix or mitigation currently meets Red Hat's criteria for deployment.
AI Analysis
Technical Summary
The vulnerability in p11-kit involves an integer overflow during the calculation of attribute-array lengths in RPC messages. This causes under-allocation of memory for nested attributes on 32-bit systems, leading to heap-based buffer overflow and memory corruption. The corrupted memory can crash the p11-kit RPC parsing process, causing a denial of service. The flaw requires local access or equivalent access to an RPC channel. Red Hat has published an advisory but currently does not provide a fix or effective mitigation that meets their standards.
Potential Impact
The primary impact is denial of service due to crashing of the p11-kit RPC parsing process. There is no confidentiality or integrity impact reported. The vulnerability is limited to 32-bit systems and requires local or RPC channel access. No known exploits are reported in the wild. The CVSS v3.1 score is 6.2 (medium severity) reflecting a low complexity local attack causing availability impact only.
Mitigation Recommendations
Red Hat currently does not offer a fix or mitigation that meets their criteria for ease of use, deployment, applicability, or stability. Users should monitor the Red Hat advisory for updates. Since no official patch or workaround is available, affected users on 32-bit systems should consider limiting access to RPC channels or upgrading to a 64-bit system where the vulnerability is not exploitable.
CVE-2026-18938: Heap-based Buffer Overflow in Red Hat Red Hat Enterprise Linux 10
Description
CVE-2026-18938 is a heap-based buffer overflow vulnerability in the p11-kit component of Red Hat Enterprise Linux 10. It arises from an integer overflow that causes miscalculation of memory allocation for nested attributes, leading to heap out-of-bounds writes. This flaw can be exploited locally or by an attacker with access to a reachable RPC channel to crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). The vulnerability is only exploitable on 32-bit systems. No official fix or mitigation currently meets Red Hat's criteria for deployment.
CVSS v3.1
Score 6.2medium
Affected software
Red Hat
Red Hat Enterprise Linux 10
Red Hat
Red Hat Enterprise Linux 6
Red Hat
Red Hat Enterprise Linux 7
Red Hat
Red Hat Enterprise Linux 8
Red Hat
Red Hat Enterprise Linux 9
Red Hat
Red Hat Hardened Images
Red Hat
Red Hat OpenShift Container Platform 4
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in p11-kit involves an integer overflow during the calculation of attribute-array lengths in RPC messages. This causes under-allocation of memory for nested attributes on 32-bit systems, leading to heap-based buffer overflow and memory corruption. The corrupted memory can crash the p11-kit RPC parsing process, causing a denial of service. The flaw requires local access or equivalent access to an RPC channel. Red Hat has published an advisory but currently does not provide a fix or effective mitigation that meets their standards.
Potential Impact
The primary impact is denial of service due to crashing of the p11-kit RPC parsing process. There is no confidentiality or integrity impact reported. The vulnerability is limited to 32-bit systems and requires local or RPC channel access. No known exploits are reported in the wild. The CVSS v3.1 score is 6.2 (medium severity) reflecting a low complexity local attack causing availability impact only.
Mitigation Recommendations
Red Hat currently does not offer a fix or mitigation that meets their criteria for ease of use, deployment, applicability, or stability. Users should monitor the Red Hat advisory for updates. Since no official patch or workaround is available, affected users on 32-bit systems should consider limiting access to RPC channels or upgrading to a 64-bit system where the vulnerability is not exploitable.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- redhat
- Date Reserved
- 2026-08-05T12:44:08.706Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-18938","vendor":"Red Hat"}]
Threat ID: 6a759a47bf8831d539075a55
Added to database: 08/07/2026, 08:41:43 UTC
Last enriched: 08/14/2026, 16:14:47 UTC
Last updated: 09/21/2026, 22:01:32 UTC
Views: 57
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