CVE-2026-98449

Status: ReceivedUnscored—

Severity—Unscored

Exploitation probability0.16 %higher than 5% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitNot knownno public code found

In the Linux kernel, the following vulnerability has been resolved:

smb: client: delete compound mids on send failure before unlock

When sending a compound request fails, smb_send_rqst() kicks off a reconnect. compound_send_recv() still has those mids on pending_mid_q, but it unlocks the server without removing them first.

During reconnect, cifs_abort_connection() walks pending_mid_q and runs each mid callback. With no response yet, those callbacks return credits and drop in_flight. Then compound_send_recv()'s send-error path returns the same credits again. in_flight ends up decremented twice and smb2_add_credits() WARNs.

Read full descriptionShow less

syzbot hits this during SMB2_negotiate when the socket send fails.

cifs_call_async() already calls delete_mid() before unlock on send failure. Do the same for compound chains and set cancelled_mid[] so the out: path does not delete them again.

CVSS

NVD hasn't assigned a CVSS score to this CVE (common since the April 2026 policy change).

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.16 %
Percentile among all scored CVEs: 5
Score date: 10/21/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Linux — Linux Kernel^AI

References

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Raw JSON (NVD)

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{
  "id": "CVE-2026-98449",
  "cveTags": [],
  "metrics": {},
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "ee258d79159afed52ca9372aeb9c1a51e89b32ee",
              "lessThan": "70783946f3b5d0c06ec7df0f5e7bec2bfad24efb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "ee258d79159afed52ca9372aeb9c1a51e89b32ee",
              "lessThan": "8f6f8a48399f82f4a83f7b9f25b9707e0062a4f9",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3c57a0be487088b08d9c88998f911eb4a7ba36e4",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4.20.11",
              "lessThan": "4.21",
              "versionType": "semver"
            }
          ],
          "programFiles": [
            "fs/smb/client/transport.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.0"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.2.9",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/smb/client/transport.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-10-18T16:16:55.237",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/70783946f3b5d0c06ec7df0f5e7bec2bfad24efb",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8f6f8a48399f82f4a83f7b9f25b9707e0062a4f9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: delete compound mids on send failure before unlock\n\nWhen sending a compound request fails, smb_send_rqst() kicks off a\nreconnect. compound_send_recv() still has those mids on pending_mid_q,\nbut it unlocks the server without removing them first.\n\nDuring reconnect, cifs_abort_connection() walks pending_mid_q and runs\neach mid callback. With no response yet, those callbacks return credits\nand drop in_flight. Then compound_send_recv()'s send-error path returns\nthe same credits again. in_flight ends up decremented twice and\nsmb2_add_credits() WARNs.\n\nsyzbot hits this during SMB2_negotiate when the socket send fails.\n\ncifs_call_async() already calls delete_mid() before unlock on send\nfailure. Do the same for compound chains and set cancelled_mid[] so the\nout: path does not delete them again."
    }
  ],
  "lastModified": "2026-10-19T10:18:54.070",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}