CVE-2026-98374ModerateLocalRevised 21 Oct

tcp: fix use-after-free of retransmit_skb_hint in tcp_send_synack()

MSRC advisory NVD CVE.org

Assessment

Severity: Moderate
CVSS base score: 7.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H/E:U
Impact: Not stated
EPSS, next 30 days: Not scored yet
Public exploit code: No Nuclei template lists it
Exploitability: Not assessed
Publicly disclosed: No
Customer action: Required: apply the update
Component: Mariner
Weakness: —
Issued by: Linux
Published: 9 Oct 2026 · October 2026
Last revised: 21 Oct 2026Information published.

CVSS 3.1 base metricsRed raises the risk · green lowers it

Attack vector: LocalAV:L
Attack complexity: LowAC:L
Privileges required: LowPR:L
User interaction: NoneUI:N
Scope: UnchangedS:U
Confidentiality: HighC:H
Integrity: NoneI:N
Availability: HighA:H

Updates that fix it

0 KBs

No KB listed

MSRC lists no downloadable update, which usually means a service-side fix or a release-notes update. Check the MSRC advisory.

Affected products

1 affected product

azl3 kernel 6.6.157.1-1 on Azure Linux 3.0

What changed

First observed 14 Oct 2026

23 Oct 2026 · 09:33:49 UTC Public exploit codeUnknown: exploit-code evidence is incomplete or retained → No Nuclei template listed
23 Oct 2026 · 09:33:49 UTC CISA KEVUnknown: catalog evidence is incomplete or retained → Not listed in the collected catalog
23 Oct 2026 · 09:33:49 UTC Source coverage: public-exploit-codeIncomplete → Current
23 Oct 2026 · 09:33:49 UTC Source coverage: first-epssIncomplete → Current
23 Oct 2026 · 09:33:49 UTC Source coverage: cisa-kevIncomplete → Current
23 Oct 2026 · 09:33:49 UTC Source coverage: msrc-cvrfIncomplete → Current
23 Oct 2026 · 08:31:50 UTC Public exploit codeNo Nuclei template listed → Unknown: exploit-code evidence is incomplete or retained
23 Oct 2026 · 08:31:50 UTC CISA KEVNot listed in the collected catalog → Unknown: catalog evidence is incomplete or retained
23 Oct 2026 · 08:31:50 UTC Source coverage: public-exploit-codeCurrent → Incomplete
23 Oct 2026 · 08:31:50 UTC Source coverage: first-epssCurrent → Incomplete
23 Oct 2026 · 08:31:50 UTC Source coverage: cisa-kevCurrent → Incomplete
23 Oct 2026 · 08:31:50 UTC Source coverage: msrc-cvrfCurrent → Incomplete

Show 5 more recent changes

21 Oct 2026 · 20:45:25 UTCLast revised 15 Oct 2026 02:50 UTC → 21 Oct 2026 18:41 UTC
18 Oct 2026 · 14:54:30 UTCLink: October 2026 → /security?release=2026-Oct#cves
15 Oct 2026 · 07:14:54 UTCLast revised 13 Oct 2026 14:54 UTC → 15 Oct 2026 02:50 UTC
14 Oct 2026 · 11:22:42 UTCLast revised 9 Oct 2026 01:04 UTC → 13 Oct 2026 14:54 UTC
14 Oct 2026 · 11:22:42 UTCSource coverage: msrc-cvrf Incomplete → Current

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Explore global source statements, affected packages and advisory history for CVE-2026-98374. The catalog has a separate collection scope from Microsoft release records.

cve-program · CVE-2026-98374

Published

Linux

Vendor product

Original vendor version evidence · not evaluated as a NuGet range

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv4/tcp_output.c"
                    ],
                    "versions": [
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "fad6d429651e748365e93ca54645accc212f0018",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "c5b4da1f403a658c1c19766be2b426003ada419f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "71d45049b0d631dfdbf3c65305f7fca676de023b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "e3ea71cb1408a013ed4e8a757b815f1a919324bd",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "631aa4cb45099f09e9385dd786bd291c6270bfc4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "0f87720c7e4bcab07c24888b3cf12bfe857bb90e",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "c31b70c9968fe9c4194d1b5d06d07596a3b680de",
                            "lessThan": "fe99bbeee5c5dbd3abc30721a8079ced59649d97",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                }

Linux

Vendor product

Original vendor version evidence · not evaluated as a NuGet range

{
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/ipv4/tcp_output.c"
                    ],
                    "versions": [
                        {
                            "version": "5.11",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.11",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.222",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.189",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.158",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.112",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.55",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.9",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }