Cyber Resilience

CVE-2026-10636

Memory Safety in Zephyrproject Zephyr 2.6.0 – 4.5.0

Public PoCMemory Safety
Published
16 June 2026
Modified
14 July 2026
Patch / advisory
CVSS Score v3.1 3.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS Score 0.0031 23th percentile
Risk Priority 16 floored blend · peak EPSS

Summary

CVE-2026-10636 is a low-severity Use After Free (CWE-416) vulnerability in Zephyrproject Zephyr. Its CVSS base score is 3.7 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 23th 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 SI-16 (Memory Protection) and CM-7 (Least Functionality) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

In Zephyr's IPv4 IGMP implementation, igmp_send() in subsys/net/ip/igmp.c read the network interface back out of the packet via net_pkt_iface(pkt) after the packet had been handed to net_send_data(). On the successful-send path the packet's last reference may already have been released…

more

by the L2 driver or by the network stack's TX handling (synchronously in the default NET_TC_TX_COUNT=0 immediate-transmit configuration), returning the net_pkt slab block to its free list. The subsequent net_pkt_iface(pkt) dereferences the freed packet, a use-after-free read; with CONFIG_NET_STATISTICS_PER_INTERFACE the resulting dangling interface pointer is further dereferenced for a statistics-counter write. The IGMP send path is reachable without authentication from inbound IPv4 IGMP membership queries addressed to 224.0.0.1 (net_ipv4_igmp_input -> send_igmp_report/send_igmp_v3_report -> igmp_send), as well as from local multicast join/leave/rejoin operations. Realistic impact is undefined behavior and potential denial of service (sporadic crash or stats corruption); a controllable write requires the asynchronous TX path plus a concurrent slab reuse. The flaw was introduced with IGMPv2 support and affects releases from v2.6.0 through v4.4.0. The fix caches the interface pointer before sending. Note the analogous IPv6 MLD path (mld_send in subsys/net/ip/ipv6_mld.c) retains the same unfixed pattern.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

UAF reachable via unauthenticated inbound IGMP packets enables remote exploitation of network stack (T1190) leading to application/system crash (T1499.004).

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-10639Same product: Zephyrproject Zephyr
CVE-2026-10646Same product: Zephyrproject Zephyr
CVE-2026-10637Same product: Zephyrproject Zephyr
CVE-2026-10638Same product: Zephyrproject Zephyr
CVE-2026-10640Same product: Zephyrproject Zephyr
CVE-2026-10655Same product: Zephyrproject Zephyr
CVE-2026-10634Same product: Zephyrproject Zephyr
CVE-2026-10663Same product: Zephyrproject Zephyr
CVE-2026-10635Same product: Zephyrproject Zephyr
CVE-2026-10667Same product: Zephyrproject Zephyr

Affected Assets

zephyrproject
zephyr
2.6.0 — 4.5.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-16 Memory Protection
  • CM-7 Least Functionality
  • SC-7 Boundary Protection
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Mitigating Controls (NIST 800-53 r5) AI

prevent

Memory protection directly blocks the use-after-free read of the freed net_pkt and its dangling interface pointer in igmp_send().

prevent

Least functionality allows disabling IGMP (or the entire IPv4 multicast stack) so the vulnerable igmp_send path is never compiled or reached.

prevent

Boundary protection can filter or drop inbound IGMP membership queries to 224.0.0.1 before they reach net_ipv4_igmp_input and trigger the send path.

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.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

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.

detects

Security testing in development can detect use-after-free bugs before release.

prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

References