Medium severity · published Aug 7, 2026
CVE-2026-18938
P11-kit: integer overflow in rpc attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems
6.2
CVSS
0.1%
EPSS
No
On KEV
Description
A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC channel, could exploit an integer overflow vulnerability. By sending specially crafted messages, the attacker can cause the system to miscalculate memory allocation for nested attributes. This leads to a memory corruption issue, specifically a heap out-of-bounds write, which can crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). This vulnerability is only exploitable on 32 bit systems.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 1% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 9 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18938
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18938
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-18938
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2478995
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