CVE-2026-43197 (GCVE-0-2026-43197)

Vulnerability from cvelistv5 – Published: 2026-05-06 11:28 – Updated: 2026-08-05 12:26
VLAI
Title
netconsole: avoid OOB reads, msg is not nul-terminated
Summary
In the Linux kernel, the following vulnerability has been resolved: netconsole: avoid OOB reads, msg is not nul-terminated msg passed to netconsole from the console subsystem is not guaranteed to be nul-terminated. Before recent commit 7eab73b18630 ("netconsole: convert to NBCON console infrastructure") the message would be placed in printk_shared_pbufs, a static global buffer, so KASAN had harder time catching OOB accesses. Now we see: printk: console [netcon_ext0] enabled BUG: KASAN: slab-out-of-bounds in string+0x1f7/0x240 Read of size 1 at addr ffff88813b6d4c00 by task pr/netcon_ext0/594 CPU: 65 UID: 0 PID: 594 Comm: pr/netcon_ext0 Not tainted 6.19.0-11754-g4246fd6547c9 Call Trace: kasan_report+0xe4/0x120 string+0x1f7/0x240 vsnprintf+0x655/0xba0 scnprintf+0xba/0x120 netconsole_write+0x3fe/0xa10 nbcon_emit_next_record+0x46e/0x860 nbcon_kthread_func+0x623/0x750 Allocated by task 1: nbcon_alloc+0x1ea/0x450 register_console+0x26b/0xe10 init_netconsole+0xbb0/0xda0 The buggy address belongs to the object at ffff88813b6d4000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 0 bytes to the right of allocated 3072-byte region [ffff88813b6d4000, ffff88813b6d4c00)
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: c62c0a17f9b7398022f9eebe547878033264f81f , < 3126a2f98beaec5a554a1fb31c46db1e8542665e (git)
Affected: c62c0a17f9b7398022f9eebe547878033264f81f , < 74ab1456eaa3b2eb986138f9e1f4cb37e73b6f58 (git)
Affected: c62c0a17f9b7398022f9eebe547878033264f81f , < 82aec772fca2223bc5774bd9af486fd95766e578 (git)
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Linux Linux Affected: 6.6
Unaffected: 0 , < 6.6 (semver)
Unaffected: 6.18.16 , ≤ 6.18.* (semver)
Unaffected: 6.19.6 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetconsole: avoid OOB reads, msg is not nul-terminated\n\nmsg passed to netconsole from the console subsystem is not guaranteed\nto be nul-terminated. Before recent\ncommit 7eab73b18630 (\"netconsole: convert to NBCON console infrastructure\")\nthe message would be placed in printk_shared_pbufs, a static global\nbuffer, so KASAN had harder time catching OOB accesses. Now we see:\n\n    printk: console [netcon_ext0] enabled\n    BUG: KASAN: slab-out-of-bounds in string+0x1f7/0x240\n    Read of size 1 at addr ffff88813b6d4c00 by task pr/netcon_ext0/594\n\n    CPU: 65 UID: 0 PID: 594 Comm: pr/netcon_ext0 Not tainted 6.19.0-11754-g4246fd6547c9\n    Call Trace:\n     kasan_report+0xe4/0x120\n     string+0x1f7/0x240\n     vsnprintf+0x655/0xba0\n     scnprintf+0xba/0x120\n     netconsole_write+0x3fe/0xa10\n     nbcon_emit_next_record+0x46e/0x860\n     nbcon_kthread_func+0x623/0x750\n\n    Allocated by task 1:\n     nbcon_alloc+0x1ea/0x450\n     register_console+0x26b/0xe10\n     init_netconsole+0xbb0/0xda0\n\n    The buggy address belongs to the object at ffff88813b6d4000\n                which belongs to the cache kmalloc-4k of size 4096\n    The buggy address is located 0 bytes to the right of\n                allocated 3072-byte region [ffff88813b6d4000, ffff88813b6d4c00)"
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    "dateReserved": "2026-05-01T14:12:55.992Z",
    "dateUpdated": "2026-08-05T12:26:28.648Z",
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Now we see:\\n\\n    printk: console [netcon_ext0] enabled\\n    BUG: KASAN: slab-out-of-bounds in string+0x1f7/0x240\\n    Read of size 1 at addr ffff88813b6d4c00 by task pr/netcon_ext0/594\\n\\n    CPU: 65 UID: 0 PID: 594 Comm: pr/netcon_ext0 Not tainted 6.19.0-11754-g4246fd6547c9\\n    Call Trace:\\n     kasan_report+0xe4/0x120\\n     string+0x1f7/0x240\\n     vsnprintf+0x655/0xba0\\n     scnprintf+0xba/0x120\\n     netconsole_write+0x3fe/0xa10\\n     nbcon_emit_next_record+0x46e/0x860\\n     nbcon_kthread_func+0x623/0x750\\n\\n    Allocated by task 1:\\n     nbcon_alloc+0x1ea/0x450\\n     register_console+0x26b/0xe10\\n     init_netconsole+0xbb0/0xda0\\n\\n    The buggy address belongs to the object at ffff88813b6d4000\\n                which belongs to the cache kmalloc-4k of size 4096\\n    The buggy address is located 0 bytes to the right of\\n                allocated 3072-byte region [ffff88813b6d4000, ffff88813b6d4c00)\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"drivers/net/netconsole.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"c62c0a17f9b7398022f9eebe547878033264f81f\",\"lessThan\":\"3126a2f98beaec5a554a1fb31c46db1e8542665e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"c62c0a17f9b7398022f9eebe547878033264f81f\",\"lessThan\":\"74ab1456eaa3b2eb986138f9e1f4cb37e73b6f58\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"c62c0a17f9b7398022f9eebe547878033264f81f\",\"lessThan\":\"82aec772fca2223bc5774bd9af486fd95766e578\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"drivers/net/netconsole.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.6\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.6\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.16\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.19.6\",\"lessThanOrEqual\":\"6.19.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H\",\"baseScore\":9.1,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.2}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-125\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.6\",\"versionEndExcluding\":\"6.18.16\",\"matchCriteriaId\":\"DD48D2A2-43CB-4E6C-A61C-C1BEA033EAF0\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.19\",\"versionEndExcluding\":\"6.19.6\",\"matchCriteriaId\":\"373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"F253B622-8837-4245-BCE5-A7BF8FC76A16\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/3126a2f98beaec5a554a1fb31c46db1e8542665e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/74ab1456eaa3b2eb986138f9e1f4cb37e73b6f58\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/82aec772fca2223bc5774bd9af486fd95766e578\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}",
    "redhat_vex": {
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      "current_release_date": "2026-07-02T12:50:37+00:00",
      "cve": "CVE-2026-43197",
      "id": "CVE-2026-43197",
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      "product_status:known_affected": "90",
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      "source": "Red Hat CSAF VEX",
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      "title": "kernel: netconsole: avoid OOB reads, msg is not nul-terminated",
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      "cve": "CVE-2026-43197",
      "id": "CVE-2026-43197",
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      "product_status:first_fixed": "2",
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      "product_status:known_not_affected": "278",
      "product_status:recommended": "172",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43197",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43197.json",
      "version": "5"
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  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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