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TI-2026-09142 Aliases CVE-2026-10640

Use-after-free reading `net_pkt` `iface` after send in IPv6 Neighbor Discovery (`ipv6_nbr.c`)

Priority LOW 31CWE-416Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Zephyr's IPv6 Neighbor Discovery send paths (net_ipv6_send_na, net_ipv6_send_ns, net_ipv6_send_rs in subsys/net/ip/ipv6_nbr.c) updated the per-interface ICMP-sent statistics by calling net_pkt_iface(pkt) after net_send_data(pkt) had already returned successfully. On the success path the network stack owns and releases the packet's reference (the L2/driver send unrefs it, e.g. ethernet_send -> net_pkt_unref), so for a freshly allocated packet with refcount 1 the net_pkt slab block can be freed before the statistics line runs (synchronously when no TX queue thread is configured, or via a concurrent TX thread otherwise). The subsequent net_pkt_iface(pkt) reads pkt->iface from the freed slab block, and with CONFIG_NET_STATISTICS_PER_INTERFACE enabled that loaded pointer is dereferenced to increment iface->stats.icmp.sent, a use-after-free (CWE-416). If the slab block was reallocated in the meantime the read/increment targets unrelated or attacker-influenced memory, yielding corrupted statistics, a fault/crash (denial of service), or potential limited memory corruption. The vulnerable Neighbor Advertisement path is reachable by any unauthenticated on-link node simply by sending ICMPv6 Neighbor Solicitations to a Zephyr node with native IPv6 enabled (handle_ns_input -> net_ipv6_send_na). Affected from v3.3.0 through v4.4.0; the fix uses the already-available iface argument instead of touching the sent packet. Configurations without per-interface statistics dereference only a global counter and are not affected by the memory-safety aspect.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0037 31st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed zephyr (zephyrproject): 4.3.1, 4.4.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
zephyrprojectzephyr3.3.0 to before 4.3.1; 4.4.0 to before 4.4.14.3.1, 4.4.1Patch availableCNA
  • zephyr Vendorzephyrproject Affected 3.3.0 to before 4.3.1; 4.4.0 to before 4.4.1 Fixed in 4.3.1, 4.4.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*3.3.0 to before 4.5.0Vulnerablezephyrproject
  • cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:* Versions 3.3.0 to before 4.5.0 Vulnerable ·zephyrproject

Remediation

  • Fix · CNA zephyr (zephyrproject) Fixed in 4.3.1, 4.4.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    zephyrproject zephyr 4.3.1, 4.4.1

    5 records Highest priority Priority LOW 5 LOW

    Other records, highest priority first

    • TI-2026-09140 Use-after-free in Zephyr ICMPv6 RX path when updating statistics after sending an echo reply or errorPriority LOW 33
    • TI-2026-09139 Use-after-free of `net_pkt` in IPv6 MLD send path triggerable by a link-local MLD QueryPriority LOW 31
    • TI-2026-09141 Use-after-free reading `net_pkt_iface()` of a sent ICMPv4 echo-reply packet in `icmpv4_handle_echo_request()`Priority LOW 22
    Show all 5 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-10640
  2. 2026-10-16 Fix available: [email protected], [email protected] · CNA

References

Exploit 1

Patch 1

  • TI-2026-04422 Out-of-bounds read/write in HTTP WebSocket upgrade via non-null-terminated Sec-WebSocket-Key CVSS 3.1CRITICAL 9.8
  • TI-2026-01361 dns: memory‑safety issue in the DNS name parser CVSS 3.1CRITICAL 9.8
  • TI-2026-09174 Unterminated URI buffer causes out-of-bounds read in LwM2M firmware pull (Package URI) CVSS 3.1CRITICAL 9.1
  • TI-2026-09168 Stack buffer overflow in `net_ipaddr_parse()` IPv4 address-with-port parsing in `subsys/net/ip/utils.c` CVSS 3.1CRITICAL 9.8
  • TI-2024-09625 net: lib: http_server: Buffer Under-read CVSS 3.1HIGH 8.6
  • TI-2021-02863 Usb bluetooth device ACL read cb buffer overflow CVSS 3.1CRITICAL 9.6
See all 196 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences