{ "cveId": "CVE-2026-31507", "url": "https://patchblox.com/security/cve/CVE-2026-31507", "summary": "CVE-2026-31507 is fixed in 12 products on 1 platform, first by DEBIAN-CVE-2026-31507, released May 15, 2026. It is not reported as exploited. Patch Radar priority: High.", "title": "net/smc: fix double-free of smc_spd_priv when tee() duplicates splice pipe buffer", "description": "In the Linux kernel, the following vulnerability has been resolved: net/smc: fix double-free of smc_spd_priv when tee() duplicates splice pipe buffer smc_rx_splice() allocates one smc_spd_priv per pipe_buffer and stores the pointer in pipe_buffer.private. The pipe_buf_operations for these buffers used .get = generic_pipe_buf_get, which only increments the page reference count when tee(2) duplicates a pipe buffer. The smc_spd_priv pointer itself was not handled, so after tee() both the original and the cloned pipe_buffer share the same smc_spd_priv *. When both pipes are subsequently released, smc_rx_pipe_buf_release() is called twice against the same object: 1st call: kfree(priv) sock_put(sk) smc_rx_update_cons() [correct] 2nd call: kfree(priv) sock_put(sk) smc_rx_update_cons() [UAF] KASAN reports a slab-use-after-free in smc_rx_pipe_buf_release(), which then escalates to a NULL-pointer dereference and kernel panic via smc_rx_update_consumer() when it chases the freed priv-\u003Esmc pointer: BUG: KASAN: slab-use-after-free in smc_rx_pipe_buf_release\u002B0x78/0x2a0 Read of size 8 at addr ffff888004a45740 by task smc_splice_tee_/74 Call Trace: \u003CTASK\u003E dump_stack_lvl\u002B0x53/0x70 print_report\u002B0xce/0x650 kasan_report\u002B0xc6/0x100 smc_rx_pipe_buf_release\u002B0x78/0x2a0 free_pipe_info\u002B0xd4/0x130 pipe_release\u002B0x142/0x160 __fput\u002B0x1c6/0x490 __x64_sys_close\u002B0x4f/0x90 do_syscall_64\u002B0xa6/0x1a0 entry_SYSCALL_64_after_hwframe\u002B0x77/0x7f \u003C/TASK\u003E BUG: kernel NULL pointer dereference, address: 0000000000000020 RIP: 0010:smc_rx_update_consumer\u002B0x8d/0x350 Call Trace: \u003CTASK\u003E smc_rx_pipe_buf_release\u002B0x121/0x2a0 free_pipe_info\u002B0xd4/0x130 pipe_release\u002B0x142/0x160 __fput\u002B0x1c6/0x490 __x64_sys_close\u002B0x4f/0x90 do_syscall_64\u002B0xa6/0x1a0 entry_SYSCALL_64_after_hwframe\u002B0x77/0x7f \u003C/TASK\u003E Kernel panic - not syncing: Fatal exception Beyond the memory-safety problem, duplicating an SMC splice buffer is semantically questionable: smc_rx_update_cons() would advance the consumer cursor twice for the same data, corrupting receive-window accounting. A refcount on smc_spd_priv could fix the double-free, but the cursor-accounting issue would still need to be addressed separately. The .get callback is invoked by both tee(2) and splice_pipe_to_pipe() for partial transfers; both will now return -EFAULT. Users who need to duplicate SMC socket data must use a copy-based read path.", "published": "2026-04-22T14:16:49Z", "severity": "Important", "cvss": 7.8, "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "epss": 0.00132, "epssPercentile": 0.0277, "priority": "High", "priorityTier": 3, "exploited": false, "vendorExploited": false, "disclosed": false, "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-31507", "fixes": [ { "platform": "linux", "product": "kernel-64kb", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-azure", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-default", "release": "sles 15.6", "fixedVersion": "6.4.0-150600.23.112.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-default", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-default-base", "release": "sles 15.6", "fixedVersion": "6.4.0-150600.23.112.1.150600.12.52.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-default-base", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1.150700.17.33.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-docs", "release": "sles 15.6", "fixedVersion": "6.4.0-150600.23.112.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-docs", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-livepatch-SLE15-SP6_Update_26", "release": "sles 15.6", "fixedVersion": "1-150600.13.3.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-livepatch-SLE15-SP7_Update_15", "release": "sles 15.7", "fixedVersion": "1-150700.15.3.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-obs-build", "release": "sles 15.6", "fixedVersion": "6.4.0-150600.23.112.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-obs-build", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-source", "release": "sles 15.6", "fixedVersion": "6.4.0-150600.23.112.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-source", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-syms", "release": "sles 15.6", "fixedVersion": "6.4.0-150600.23.112.1", "fix": "SUSE-SU-2026:2195-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2195-1", "released": "2026-07-01T08:17:32Z" }, { "platform": "linux", "product": "kernel-syms", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "kernel-zfcpdump", "release": "sles 15.7", "fixedVersion": "6.4.0-150700.53.55.1", "fix": "SUSE-SU-2026:2238-1", "url": "https://patchblox.com/security/fix/linux/suse-su-2026-2238-1", "released": "2026-06-30T10:03:11Z" }, { "platform": "linux", "product": "linux", "release": "Debian 12.15 (bookworm)", "fixedVersion": "6.1.170-1", "fix": "DEBIAN-CVE-2026-31507", "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-31507", "released": "2026-05-15T16:01:09Z" }, { "platform": "linux", "product": "linux", "release": "Debian 13.5 (trixie)", "fixedVersion": "6.12.85-1", "fix": "DEBIAN-CVE-2026-31507", "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-31507", "released": "2026-05-15T16:01:09Z" }, { "platform": "linux", "product": "linux", "release": "Debian 14", "fixedVersion": "6.19.11-1", "fix": "DEBIAN-CVE-2026-31507", "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-31507", "released": "2026-05-15T16:01:09Z" } ], "noFixYet": [], "dataAsOf": "2026-11-09T01:18:40Z", "attribution": { "text": "Data: Patchblox Patch Radar", "url": "https://patchblox.com/security/patch-radar", "terms": "https://patchblox.com/security/patch-radar/use-the-data" } }