CVE-2026-99126 (GCVE-0-2026-99126)

Vulnerability from cvelistv5 – Published: 2026-10-28 10:34 – Updated: 2026-10-30 12:41
VLAI
Title
s390/ctcm: Prevent XID null dereference
Summary
In the Linux kernel, the following vulnerability has been resolved: s390/ctcm: Prevent XID null dereference The mpc_validate_xid() function sets grp->saved_xid2->xid2_flag2 to 0x40 to signal XID validation error. If peer XID is NULL or r/w channel pairing mismatch happens, grp->saved_xid2 is never initialized. An attempt to set the flag in such case leads to NULL dereference. Fix this by using the always available priv->xid->xid2_flag2 instead of grp->saved_xid2->xid2_flag2 for validation errors.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6643 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < f9d9e2dadc9fbdfe01aeb6581978c3b59092919e (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < a7c3e1795e4fe5e6680cab7cd7eee0503b00a248 (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < c11e435d334e4c311eaaf721e179a5ca6852c221 (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < 977dac6cc5531a8e058df05b6af94406b940cb9e (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < 1525fb6e2f9f9a2c8c8723ee0959b1130a6b8213 (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < 34fa3607b7604b3052b19cec8b0ad644818cdd2a (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < 8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < b264d8422779d69febce914efc47a92a85cc382c (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.26
Unaffected: 0 , < 2.6.26 (semver)
Unaffected: 5.10.273 , ≤ 5.10.* (semver)
Unaffected: 5.15.224 , ≤ 5.15.* (semver)
Unaffected: 6.1.191 , ≤ 6.1.* (semver)
Unaffected: 6.6.161 , ≤ 6.6.* (semver)
Unaffected: 6.12.115 , ≤ 6.12.* (semver)
Unaffected: 6.18.59 , ≤ 6.18.* (semver)
Unaffected: 7.2.13 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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    "datePublished": "2026-10-28T10:34:40.661Z",
    "dateReserved": "2026-09-25T10:25:14.393Z",
    "dateUpdated": "2026-10-30T12:41:59.971Z",
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      "cve": "CVE-2026-99126",
      "id": "CVE-2026-99126",
      "initial_release_date": "2026-10-28T10:34:40.661000+00:00",
      "product_status:known_affected": "112",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: kernel: Denial of service via null pointer dereference in s390/ctcm",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-99126.json",
      "version": "3"
    }
  }
}



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