Raw vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-10635 is a medium-severity Use After Free (CWE-416) vulnerability in Zephyrproject Zephyr. Its CVSS base score is 6.3 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked at the 6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-37036
Vulnerability Data
On Xtensa targets with CONFIG_USERSPACE and CONFIG_XTENSA_MMU, the page-table code (arch/xtensa/core/ptables.c) maintains a global list, xtensa_domain_list, of active memory domains using a list node embedded inside the caller-owned struct k_mem_domain. When a domain is destroyed via k_mem_domain_deinit() -> arch_mem_domain_deinit(), the…
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page tables are torn down and domain->arch.ptables is set to NULL, but the domain's node was not removed from xtensa_domain_list. The freed/deinitialized domain therefore remained linked into the global list as a dangling pointer into caller-owned storage that may then be freed or reused. Any subsequent arch_mem_map()/arch_mem_unmap() operation (widely invoked by kernel memory-mapping and demand-paging code) traverses the stale node and dereferences domain->ptables: at minimum a NULL pointer dereference causing a fatal MMU exception (denial of service), and if the k_mem_domain storage has been freed or reused, a use-after-free in which a stale/controlled ptables value is dereferenced and written through during the page-table walk (l2_page_table_map writes l1_table[...] and l2_table[...], and xtensa_mmu_compute_domain_regs writes into the domain struct and the L1 table), yielding page-table memory corruption that can undermine userspace isolation. The vulnerable path is reachable only from privileged kernel/supervisor code (k_mem_domain_deinit is not a syscall), not directly from unprivileged user threads or remotely. Affected: Zephyr v4.4.0 (the Xtensa memory-domain de-initialization feature was introduced in commit 3032b58f52d and first shipped in v4.4.0); fixed on main by adding sys_slist_find_and_remove() in arch_mem_domain_deinit(). The Xtensa MPU path is unaffected.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 3 hardening rules · 3 OS baselines
V1.4.3
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover use-after-free bugs through dynamic analysis or fuzzing.
Engineering principles can require memory-safe constructs or languages that structurally avoid introducing use-after-free.
Process isolation confines the blast radius of use-after-free memory corruption to a single execution domain.
Memory protection controls limit exploitation impact by blocking unauthorized code execution from dangling pointers.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.
Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.
Routine patching removes known use-after-free instances after they have been introduced in released software.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development can detect use-after-free bugs before release.
Secure SDLC mandates memory-safety practices that reduce use-after-free defects.
Application security requirements can specify memory-management rules that mitigate use-after-free.
Secure architecture principles include memory-safety design choices that limit use-after-free exposure.
Secure coding standards directly prescribe avoidance of use-after-free patterns.
Change-management processes help ensure memory-safety fixes are deployed consistently.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248592 OL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 8 (1 rule)
- V-230279 RHEL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 9 (1 rule)
- V-257794 RHEL 9 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416