CVE-2026-18938
P11-kit: integer overflow in rpc attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
6.2
P11-kit: integer overflow in rpc attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems
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.
- Record
CVE-2026-18938- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-122
- Updated
- 2026-11-02
EUVDEUVD-2026-54413
6.2
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.
- Record
EUVD-2026-54413- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6x8p-h5fj-5ppr
6.2
A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC...
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.
- Record
GHSA-6x8p-h5fj-5ppr- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-122
- Updated
- 2026-11-02
NVD
6.2
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.
- Record
CVE-2026-18938- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-122
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-18938
6.2
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.
- Record
DEBIAN-CVE-2026-18938- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVOESA-2026-3503
6.2
p11-kit security update
Provides a way to load and enumerate PKCS#11 modules. Provides a standard configuration setup for installing PKCS#11 modules in such a way that they're discoverable. Also solves problems with coordinating the use of PKCS#11 by different components or libraries living in the same process.
Security Fix(es):
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.(CVE-2026-18938)
- Record
OESA-2026-3503- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Show 11 moreShow less
OSVUBUNTU-CVE-2026-18938
6.2
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.
- Record
UBUNTU-CVE-2026-18938- CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVAZL-95481 No score
CVE-2026-18938 affecting package p11-kit for versions less than 0.26.5-1
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.
- Record
AZL-95481- Updated
- 2026-11-02
OSVMGASA-2026-0460 No score
Updated p11-kit packages fix security vulnerabilities
The updated packages fix security vulnerabilities: Stack exhaustion via unbounded recursion in rpc attribute parsing. (CVE-2026-13757) Integer overflow in rpc attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems. (CVE-2026-18938)
- Record
MGASA-2026-0460- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:11862-1 No score
libp11-kit0-0.26.5-1.1 on GA media
These are all security issues fixed in the libp11-kit0-0.26.5-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:11862-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:22105-1 No score
Security update for p11-kit
This update for p11-kit fixes the following issues:
- CVE-2026-13757: Stack exhaustion via unbounded recursion in RPC attribute parsing (bsc#1269664).
- CVE-2026-18938: integer overflow in RPC attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems (bsc#1280702).
- Record
openSUSE-SU-2026:22105-1- Updated
- 2026-11-02
OSVROOT-OS-DEBIAN-11-CVE-2026-18938 No score
CVE-2026-18938 in p11-kit - Patched by Root
Root has patched CVE-2026-18938 in the p11-kit package for Root:Debian:11. Multiple fixed versions available.
- Record
ROOT-OS-DEBIAN-11-CVE-2026-18938- Updated
- 2026-11-02
OSVROOT-OS-DEBIAN-12-CVE-2026-18938 No score
CVE-2026-18938 in p11-kit - Patched by Root
Root has patched CVE-2026-18938 in the p11-kit package for Root:Debian:12. Multiple fixed versions available.
- Record
ROOT-OS-DEBIAN-12-CVE-2026-18938- Updated
- 2026-11-02
OSVROOT-OS-DEBIAN-13-CVE-2026-18938 No score
CVE-2026-18938 in p11-kit - Patched by Root
Root has patched CVE-2026-18938 in the p11-kit package for Root:Debian:13. Multiple fixed versions available.
- Record
ROOT-OS-DEBIAN-13-CVE-2026-18938- Updated
- 2026-11-02
OSVSUSE-SU-2026:24193-1 No score
Security update for p11-kit
This update for p11-kit fixes the following issues:
- CVE-2026-13757: Stack exhaustion via unbounded recursion in RPC attribute parsing (bsc#1269664).
- CVE-2026-18938: integer overflow in RPC attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems (bsc#1280702).
- Record
SUSE-SU-2026:24193-1- Updated
- 2026-11-02
OSVSUSE-SU-2026:24255-1 No score
Security update for p11-kit
This update for p11-kit fixes the following issues:
- CVE-2026-13757: Stack exhaustion via unbounded recursion in RPC attribute parsing (bsc#1269664).
- CVE-2026-18938: integer overflow in RPC attribute-array length calculation can under-allocate nested attribute storage on 32 bit systems (bsc#1280702).
- Record
SUSE-SU-2026:24255-1- Updated
- 2026-11-02
OSVUSN-8687-1 No score
p11-kit vulnerabilities
It was discovered that p11-kit incorrectly handled certain RPC messages. A local attacker could use this issue to cause p11-kit to crash, resulting in a denial of service. (CVE-2026-13757)
It was discovered that p11-kit incorrectly handled nested attribute decoding on 32-bit systems. A local attacker could use this issue to cause p11-kit to crash, resulting in a denial of service. (CVE-2026-18938)
- Record
USN-8687-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
p11-kitAzure Linux:3 |
before 0.26.5-1 | 0.26.5-1 |
p11-kitDebian:12 |
All versions, plus listed versions 0.24.1-20.24.1-2+loong640.25.0-10.25.0-20.25.0-3 Show 20 moreShow less0.25.0-40.25.0-50.25.1-10.25.10-10.25.2-10.25.3-10.25.3-20.25.3-30.25.3-40.25.3-50.25.5-10.25.5-20.25.5-30.25.9-10.25.9-20.26.2-10.26.2-20.26.2-30.26.4-10.26.5-1 |
None known |
p11-kitDebian:13 |
All versions, plus listed versions 0.25.10-10.25.5-30.25.9-10.25.9-20.26.2-1 Show 4 moreShow less0.26.2-20.26.2-30.26.4-10.26.5-1 |
None known |
p11-kitDebian:14 |
before 0.26.5-1, plus listed versions 0.25.10-10.25.5-30.25.9-10.25.9-20.26.2-10.26.2-20.26.2-30.26.4-1 |
0.26.5-1 |
p11-kitMageia:10 From an advisory covering 2 CVEs |
before 0.25.10-1.1.mga10 | 0.25.10-1.1.mga10 |
p11-kitopenEuler:24.03-LTS-SP3 |
before 0.25.0-3.oe2403sp3 | 0.25.0-3.oe2403sp3 |
p11-kitopenEuler:24.03-LTS-SP4 |
before 0.25.0-3.oe2403sp4 | 0.25.0-3.oe2403sp4 |
p11-kitopenEuler:20.03-LTS-SP4 |
before 0.23.20-6.oe2003sp4 | 0.23.20-6.oe2003sp4 |
p11-kitopenEuler:22.03-LTS-SP4 |
before 0.24.0-3.oe2203sp4 | 0.24.0-3.oe2203sp4 |
p11-kitopenEuler:24.03-LTS-SP1 |
before 0.25.0-3.oe2403sp1 | 0.25.0-3.oe2403sp1 |
Show 20 moreShow less
| Package | Affected | Fixed |
|---|---|---|
p11-kitRoot:Debian:11 |
before 0.23.22-1.aikido.1 | 0.23.22-1.aikido.1 |
rootio-p11-kitRoot:Debian:11 |
before 0.23.22-1.aikido.1 | 0.23.22-1.aikido.1 |
p11-kitRoot:Debian:12 |
before 0.24.1-2.aikido.3 | 0.24.1-2.aikido.3 |
rootio-p11-kitRoot:Debian:12 |
before 0.24.1-2.aikido.3 | 0.24.1-2.aikido.3 |
p11-kitRoot:Debian:13 |
before 0.25.5-3.aikido.3 | 0.25.5-3.aikido.3 |
rootio-p11-kitRoot:Debian:13 |
before 0.25.5-3.aikido.3 | 0.25.5-3.aikido.3 |
p11-kitSUSE:Linux Micro 6.2 From an advisory covering 2 CVEs |
before 0.25.5-160000.3.1 | 0.25.5-160000.3.1 |
p11-kitSUSE:Linux Enterprise Server 16.0 From an advisory covering 2 CVEs |
before 0.25.5-160000.3.1 | 0.25.5-160000.3.1 |
p11-kitSUSE:Linux Enterprise Server for SAP applications 16.0 From an advisory covering 2 CVEs |
before 0.25.5-160000.3.1 | 0.25.5-160000.3.1 |
p11-kitUbuntu:Pro:18.04:LTS |
before 0.23.9-2ubuntu0.1+esm1, plus listed versions 0.23.7-30.23.9-20.23.9-2ubuntu0.1 |
0.23.9-2ubuntu0.1+esm1 |
p11-kitUbuntu:Pro:20.04:LTS |
before 0.23.20-1ubuntu0.1+esm1, plus listed versions 0.23.17-20.23.18.1-20.23.19-20.23.20-10.23.20-1build10.23.20-1ubuntu0.1 |
0.23.20-1ubuntu0.1+esm1 |
p11-kitUbuntu:22.04:LTS |
before 0.24.0-6ubuntu0.1, plus listed versions 0.23.22-1build10.24.0-50.24.0-60.24.0-6build1 |
0.24.0-6ubuntu0.1 |
p11-kitUbuntu:24.04:LTS |
before 0.25.3-4ubuntu2.2, plus listed versions 0.25.0-4ubuntu10.25.3-2ubuntu20.25.3-4ubuntu10.25.3-4ubuntu20.25.3-4ubuntu2.1 |
0.25.3-4ubuntu2.2 |
p11-kitUbuntu:26.04:LTS |
All versions, plus listed versions 0.25.5-3ubuntu10.25.9-20.25.10-10.25.10-1ubuntu10.26.2-2 |
None known |
p11-kitUbuntu:Pro:18.04:LTS From an advisory covering 2 CVEs |
before 0.23.9-2ubuntu0.1+esm1, plus listed versions 0.23.7-30.23.9-20.23.9-2ubuntu0.1 |
0.23.9-2ubuntu0.1+esm1 |
p11-kitUbuntu:Pro:20.04:LTS From an advisory covering 2 CVEs |
before 0.23.20-1ubuntu0.1+esm1, plus listed versions 0.23.17-20.23.18.1-20.23.19-20.23.20-10.23.20-1build10.23.20-1ubuntu0.1 |
0.23.20-1ubuntu0.1+esm1 |
p11-kitUbuntu:22.04:LTS From an advisory covering 2 CVEs |
before 0.24.0-6ubuntu0.1, plus listed versions 0.23.22-1build10.24.0-50.24.0-60.24.0-6build1 |
0.24.0-6ubuntu0.1 |
p11-kitUbuntu:24.04:LTS From an advisory covering 2 CVEs |
before 0.25.3-4ubuntu2.2, plus listed versions 0.25.0-4ubuntu10.25.3-2ubuntu20.25.3-4ubuntu10.25.3-4ubuntu20.25.3-4ubuntu2.1 |
0.25.3-4ubuntu2.2 |
p11-kitopenSUSE:Tumbleweed From an advisory covering 2 CVEs |
before 0.26.5-1.1 | 0.26.5-1.1 |
p11-kitopenSUSE:Leap 16.0 From an advisory covering 2 CVEs |
before 0.25.5-160000.3.1 | 0.25.5-160000.3.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-18938 is a medium vulnerability (CVSS 6.2) in Red Hat Enterprise Linux 10, published August 7, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.11%, the 1st percentile. Fixed in p11-kit 0.26.5-1.
References
access.redhat.com/security/cve/CVE-2026-18938
bugzilla.redhat.com/show_bug.cgi?id=2478995
nvd.nist.gov/vuln/detail/CVE-2026-18938
github.com/advisories/GHSA-6x8p-h5fj-5ppr
security-tracker.debian.org/tracker/CVE-2026-18938
advisories.mageia.org/MGASA-2026-0460.html
Show 16 moreShow less
bugs.mageia.org/show_bug.cgi?id=35906
lists.fedoraproject.org/archives/list/[email protected]/message/Q6TQ5QWOGE7ZBPZGVINQXHGKAYSV4IMF
bugzilla.redhat.com/show_bug.cgi?id=2494556
github.com/p11-glue/p11-kit/issues/767
lists.fedoraproject.org/archives/list/[email protected]/message/AD5OWYEURQQ756QI27UWHAMDLD5B6WGZ
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2026-3503
suse.com/support/update/announcement/2026/suse-su-202624193-1
bugzilla.suse.com/1269664
bugzilla.suse.com/1280702
suse.com/security/cve/CVE-2026-13757
suse.com/security/cve/CVE-2026-18938
suse.com/support/update/announcement/2026/suse-su-202624255-1
ubuntu.com/security/CVE-2026-18938
cve.org/CVERecord?id=CVE-2026-18938
ubuntu.com/security/notices/USN-8687-1
ubuntu.com/security/CVE-2026-13757