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

Vulnerability from cvelistv5 – Published: 2026-10-28 10:34 – Updated: 2026-10-28 10:34
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 7034 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < 34fa3607b7604b3052b19cec8b0ad644818cdd2a (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < 8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab (git)
Affected: 293d984f0e3604c04dcdbf00117ddc1e5d4b1909 , < b264d8422779d69febce914efc47a92a85cc382c (git)
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Linux Linux Affected: 2.6.26
Unaffected: 0 , < 2.6.26 (semver)
Unaffected: 6.18.59 , ≤ 6.18.* (semver)
Unaffected: 7.2.13 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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          "programFiles": [
            "drivers/s390/net/ctcm_mpc.c"
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              "operator": "OR"
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/ctcm: Prevent XID null dereference\n\nThe mpc_validate_xid() function sets grp-\u003esaved_xid2-\u003exid2_flag2 to 0x40\nto signal XID validation error. If peer XID is NULL or r/w channel\npairing mismatch happens, grp-\u003esaved_xid2 is never initialized. An\nattempt to set the flag in such case leads to NULL dereference.\n\nFix this by using the always available priv-\u003exid-\u003exid2_flag2 instead of\ngrp-\u003esaved_xid2-\u003exid2_flag2 for validation errors."
        }
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      "providerMetadata": {
        "dateUpdated": "2026-10-28T10:34:40.661Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/b264d8422779d69febce914efc47a92a85cc382c"
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-99126",
    "datePublished": "2026-10-28T10:34:40.661Z",
    "dateReserved": "2026-09-25T10:25:14.393Z",
    "dateUpdated": "2026-10-28T10:34:40.661Z",
    "state": "PUBLISHED"
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        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/ctcm: Prevent XID null dereference\n\nThe mpc_validate_xid() function sets grp-\u003esaved_xid2-\u003exid2_flag2 to 0x40\nto signal XID validation error. If peer XID is NULL or r/w channel\npairing mismatch happens, grp-\u003esaved_xid2 is never initialized. An\nattempt to set the flag in such case leads to NULL dereference.\n\nFix this by using the always available priv-\u003exid-\u003exid2_flag2 instead of\ngrp-\u003esaved_xid2-\u003exid2_flag2 for validation errors."
          }
        ],
        "id": "CVE-2026-99126",
        "lastModified": "2026-10-28T11:17:32.317",
        "metrics": {},
        "published": "2026-10-28T11:17:32.317",
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        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
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}



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