CVE-2026-63836 batman-adv: tp_meter: avoid divide-by-zero for dec_cwnd

🗓️ 19 Jul 2026 12:02:27Reported by LinuxType

batman-adv tp_meter fixes divide-by-zero by using safe 32-bit arithmetic for cwnd with (mss**2)*8/cwnd.

Reporter	Title	Published	Views	Family All 11
ATTACKERKB	CVE-2026-63836	19 Jul 202612:02	–	attackerkb
Circl	CVE-2026-63836	19 Jul 202616:12	–	circl
CVE	CVE-2026-63836	19 Jul 202612:02	–	cve
EUVD	EUVD-2026-45502	19 Jul 202612:02	–	euvd
NVD	CVE-2026-63836	19 Jul 202612:16	–	nvd
OSV	CVE-2026-63836 batman-adv: tp_meter: avoid divide-by-zero for dec_cwnd	19 Jul 202612:02	–	osv
OSV	DEBIAN-CVE-2026-63836	19 Jul 202612:16	–	osv
OSV	UBUNTU-CVE-2026-63836	20 Jul 202600:00	–	osv
Positive Technologies	PT-2026-61152	19 Jul 202600:00	–	ptsecurity
SUSE CVE	SUSE CVE-2026-63836	19 Jul 202617:34	–	susecve

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/batman-adv/tp_meter.c"
    ],
    "versions": [
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "35264c4d46067d6312871488c810cef387f8c1f6",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "1381b021bf886b793fa5ffb895a8efae7ba0318f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "d08b69da40a101df1e28bfe1e8fa7a09ffa41107",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "cd74176cf1685f35a2e5f212d15748bbfecb53b6",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "ac229c86e49fdb96d91f51bc2fa37a9c4f58c44f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "7d2a44bc6bbe39aed03c68864aa0e54e04a50278",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "585616dab0aa9c45bc11b2c8082ca78533bc00e9",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e",
        "lessThan": "33ccd52f3cc9ed46ce395199f89aa3234dc83314",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/batman-adv/tp_meter.c"
    ],
    "versions": [
      {
        "version": "4.8",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "4.8",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "5.10.260",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "5.15.211",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "6.1.177",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "6.6.144",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "6.12.95",
        "lessThanOrEqual": "6.12.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "6.18.38",
        "lessThanOrEqual": "6.18.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "7.1.3",
        "lessThanOrEqual": "7.1.*",
        "status": "unaffected",
        "versionType": "semver"
      },
      {
        "version": "7.2-rc1",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]

Source	Link
git	www.git.kernel.org/stable/c/7d2a44bc6bbe39aed03c68864aa0e54e04a50278
git	www.git.kernel.org/stable/c/ac229c86e49fdb96d91f51bc2fa37a9c4f58c44f
git	www.git.kernel.org/stable/c/1381b021bf886b793fa5ffb895a8efae7ba0318f
git	www.git.kernel.org/stable/c/cd74176cf1685f35a2e5f212d15748bbfecb53b6
git	www.git.kernel.org/stable/c/585616dab0aa9c45bc11b2c8082ca78533bc00e9
git	www.git.kernel.org/stable/c/d08b69da40a101df1e28bfe1e8fa7a09ffa41107
git	www.git.kernel.org/stable/c/33ccd52f3cc9ed46ce395199f89aa3234dc83314
git	www.git.kernel.org/stable/c/35264c4d46067d6312871488c810cef387f8c1f6

19 Jul 2026 12:02Current