boxscore/security
CVE · referencelatest edition

Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-23095

Linux Linux — gue: Fix skb memleak with inner IP protocol 0.
  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  N  N  H    5.5   .0030   21.1     —
AFFECTED
  Product  Versions                                    Fixed
  Linux    37dd0247797b168ad1cc7f5dbec825a1ee66535b –  —
  Linux    3.18 –                                      5.10.249
TIMELINE
  Jan 13  Reserved by Linux
  Feb 4   Published (CNA: Linux)
  Oct 15  RESCORED — CVE-2026-23095 (Linux). CVSS 7.5 → 5.5 (NVD).
CWE-401 · CNA: Linux · CVSS v3.1 · 9 references · NVD status: Modified

Description

In the Linux kernel, the following vulnerability has been resolved: gue: Fix skb memleak with inner IP protocol 0. syzbot reported skb memleak below. [0] The repro generated a GUE packet with its inner protocol 0. gue_udp_recv() returns -guehdr->proto_ctype for "resubmit" in ip_protocol_deliver_rcu(), but this only works with non-zero protocol number. Let's drop such packets. Note that 0 is a valid number (IPv6 Hop-by-Hop Option). I think it is not practical to encap HOPOPT in GUE, so once someone starts to complain, we could pass down a resubmit flag pointer to distinguish two zeros from the upper layer: * no error * resubmit HOPOPT [0] BUG: memory leak unreferenced object 0xffff888109695a00 (size 240): comm "syz.0.17", pid 6088, jiffies 4294943096 hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 40 c2 10 81 88 ff ff 00 00 00 00 00 00 00 00 .@.............. backtrace (crc a84b336f): kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline] slab_post_alloc_hook mm/slub.c:4958 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270 __build_skb+0x23/0x60 net/core/skbuff.c:474 build_skb+0x20/0x190 net/core/skbuff.c:490 __tun_build_skb drivers/net/tun.c:1541 [inline] tun_build_skb+0x4a1/0xa40 drivers/net/tun.c:1636 tun_get_user+0xc12/0x2030 drivers/net/tun.c:1770 tun_chr_write_iter+0x71/0x120 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x45d/0x710 fs/read_write.c:686 ksys_write+0xa7/0x170 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
January 13, 2026ReservedReserved by Linux
February 4, 2026PublishedPublished (CNA: Linux)
October 15, 2026RESCOREDRESCORED — CVE-2026-23095 (Linux). CVSS 7.5 → 5.5 (NVD).

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux—37dd0247797b168ad1cc7f5dbec825a1ee66535b—
LinuxLinux—3.185.10.249

Weaknesses

CWE-401

References (9)

Related

Authoritative record: CVE-2026-23095 at cve.org

Vendors: linux

Weaknesses: CWE-401

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-23095 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.