# CVE-2026-13757: p11-kit stack exhaustion via uncontrolled recursion in RPC attribute parsing

Source: https://junglewise.ai/threats/cve-2026-13757-p11-kit-stack-exhaustion-via-uncontrolled-recursion-in-rpc  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-29. Updated: 2026-06-29  
License: CC BY 4.0 with a link back

CVE-2026-13757 · Severity: medium · CVSS 6.2 · Published 2026-06-29

A security flaw in p11-kit, a tool used to manage security modules like smart cards and encryption keys, can allow a local user to crash the service. By sending a specially crafted request, an attacker can force the system to run out of memory and stop responding. This results in a denial of service for critical applications that rely on p11-kit, such as web browsers, VPN clients, and SSH agents.

Technologies: [Red Hat Enterprise Linux 10](https://junglewise.ai/threats/technologies/enterprise-linux-10), [Red Hat Enterprise Linux 6](https://junglewise.ai/threats/technologies/enterprise-linux-6), [Red Hat Enterprise Linux 7](https://junglewise.ai/threats/technologies/enterprise-linux-7), [Red Hat Enterprise Linux 8](https://junglewise.ai/threats/technologies/enterprise-linux-8), [Red Hat Enterprise Linux 9](https://junglewise.ai/threats/technologies/enterprise-linux-9), [Red Hat OpenShift Container Platform 4](https://junglewise.ai/threats/technologies/openshift-container-platform-4). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-13757 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-13757 being exploited in the wild.

**How severe is CVE-2026-13757?** Medium severity, with a CVSS score of 6.2, published 29 June 2026.

**Which products and versions are affected?** p11-kit p11-kit Introduced in commit 6529b540 (Feb 2024); Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 9; Red Hat Red Hat Enterprise Linux 8; and 3 more.

**Is there a fix for CVE-2026-13757?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-13757 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-13757?** Check whether you run Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 or one of the others listed. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A flaw exists in p11-kit's RPC message attribute parsing functions, specifically p11_rpc_message_get_attribute() and p11_rpc_message_get_attribute_array_value(). These functions form a mutually-recursive call chain without a recursion depth limit when processing nested CKA_WRAP_TEMPLATE, CKA_UNWRAP_TEMPLATE, and CKA_DERIVE_TEMPLATE attributes. An unauthenticated local attacker with access to the p11-kit RPC Unix domain socket can send a crafted C_CreateObject request with deeply nested template attributes. This triggers stack exhaustion, leading to a SIGSEGV/SIGBUS crash of the p11-kit server process and any dependent services. The vulnerability was introduced in commit 6529b540.

## Affected products

- p11-kit p11-kit Introduced in commit 6529b540 (Feb 2024)
- Red Hat Red Hat Enterprise Linux 10
- Red Hat Red Hat Enterprise Linux 9
- Red Hat Red Hat Enterprise Linux 8
- Red Hat Red Hat Enterprise Linux 7
- Red Hat Red Hat Enterprise Linux 6
- Red Hat Red Hat OpenShift Container Platform 4

## Timeline

- 2026-06-29: disclosed
- 2026-06-29: advisory

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-13757](https://access.redhat.com/security/cve/CVE-2026-13757)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2494556](https://bugzilla.redhat.com/show_bug.cgi?id=2494556)

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