{
  "cveId": "CVE-2026-90100",
  "url": "https://patchblox.com/security/cve/CVE-2026-90100",
  "summary": "CVE-2026-90100 is fixed in linux on 1 platform by DEBIAN-CVE-2026-90100 (version 7.2.6-1), released September 23, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "ptp: netc: fix period truncation and potential divide-by-zero in PEROUT",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  ptp: netc: fix period truncation and potential divide-by-zero in PEROUT  The max_period bound in net_timer_enable_perout() was computed as:    max_period = (u64)NETC_TMR_DEFAULT_FIPER \u002B integral_period;  which exceeds U32_MAX when integral_period \u003E 0 (e.g. 0x100000002 for the default 333333333 Hz clock). A period_ns that passes this check but exceeds U32_MAX is then silently truncated when stored into the u32 struct netc_pp::period field.  A truncated value of zero can reach netc_timer_set_perout_alarm(), where the local u32 period variable would also be 0, causing a divide-by-zero in roundup_u64(delta, period) whenever the stime \u003C min_time branch is taken (which always happens for a start time of {0, 0}).  Additionally, netc_timer_enable_periodic_pulse() and netc_timer_enable_fiper() both compute:    fiper = pp-\u003Eperiod - integral_period;  A zero pp-\u003Eperiod results in an unsigned wraparound to 0xFFFFFFFD, mis-programming the FIPER hardware register.  Fix all three issues by capping max_period at NETC_TMR_DEFAULT_FIPER (0xFFFFFFFF). This ensures that any period_ns passing the range check fits in a u32 without truncation, so the stored value is always valid and non-zero. The accepted range is reduced by integral_period ns (typically only a few nanoseconds), which is negligible in practice.",
  "published": "2026-09-17T17:17:01Z",
  "severity": "",
  "epss": 0.00206,
  "epssPercentile": 0.10785,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-90100",
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-90100",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-90100",
      "released": "2026-09-23T19:19:02Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T00:53:09Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}