CVE-2026-98044

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98044", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:19:56.071Z", "datePublished": "2026-09-25T10:23:55.454Z", "dateUpdated": "2026-10-21T12:54:12.833Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:54:12.833Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject legacy packet loads from callbacks\n\ncheck_ld_abs() models a failed BPF_LD_ABS or BPF_LD_IND in a\nsubprogram as an implicit return with R0 set to zero. It calls\nprepare_func_exit() to explore this synthesized path.\n\nWhen the load is reached directly from a synchronous callback,\nprepare_func_exit() enforces the callback return contract and marks R0\nprecise. R0 is not derived from a real instruction on this path, so\nprecision backtracking reaches the callback call with R0 still requested\nand triggers the \"callback unexpected regs\" verifier bug. A privileged\nprogram loader can therefore cause a verifier warning and an -EFAULT\nBPF_PROG_LOAD.\n\nThese legacy packet-load instructions are deprecated. Reject them from\ncallbacks rather than complicating their implicit-return model. Check all\nactive frames before constructing the implicit return so nested static\nsubprograms cannot hide the callback context.\n\nGlobal functions are verified independently with a fresh frame zero, so\nan active-frame check cannot identify a global function called from a\ncallback. Also check the complete subprogram call graph during stack-depth\nvalidation and reject a function containing a legacy load when any caller\nis a callback. This covers global and static descendants without making\nhas_ld_abs transitive, preserving its per-function BTF return-type check.\nOrdinary uses outside callbacks remain supported."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/bpf/verifier.c"], "versions": [{"version": "8674e2db06cff6b50f2216eed9a761d15425bb34", "lessThan": "cebda2a2bb4183550eae9dcf888c16407b4fffda", "status": "affected", "versionType": "git"}, {"version": "ce01a4e5cfac7adbe0be565f90cd32ecbb2f8337", "lessThan": "3484a99303912db62428494a9061212049027e57", "status": "affected", "versionType": "git"}, {"version": "ee861486e377edc55361c08dcbceab3f6b6577bd", "lessThan": "bc489c0c9b8c86bd7fac42cfd1bb152f042fca56", "status": "affected", "versionType": "git"}, {"version": "ee861486e377edc55361c08dcbceab3f6b6577bd", "lessThan": "e7d28823c662128caae63f14e16bd394916c139b", "status": "affected", "versionType": "git"}, {"version": "928d354ae3557e8f755a227e67be88034eb3cd7f", "status": "affected", "versionType": "git"}, {"version": "8a800497d9f6c2ec9c2c1ba7b71d0ac2ea7f7bbe", "status": "affected", "versionType": "git"}, {"version": "de1055e7f9e67af32b1f3376066272b04e5223c0", "status": "affected", "versionType": "git"}, {"version": "37ad2bb11e9de92cb7b94548705eeedd87f7d392", "status": "affected", "versionType": "git"}, {"version": "d846d83bdacbd8f14fc45c63b8c1d22608452e1c", "status": "affected", "versionType": "git"}, {"version": "6.12.101", "lessThan": "6.12.114", "status": "affected", "versionType": "semver"}, {"version": "6.18.42", "lessThan": "6.18.53", "status": "affected", "versionType": "semver"}, {"version": "5.10.265", "lessThan": "5.11", "status": "affected", "versionType": "semver"}, {"version": "5.15.216", "lessThan": "5.16", "status": "affected", "versionType": "semver"}, {"version": "6.1.183", "lessThan": "6.2", "status": "affected", "versionType": "semver"}, {"version": "6.6.148", "lessThan": "6.7", "status": "affected", "versionType": "semver"}, {"version": "7.0.10", "lessThan": "7.1", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/bpf/verifier.c"], "versions": [{"version": "7.1", "status": "affected"}, {"version": "0", "lessThan": "7.1", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.7", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.101", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.42", "versionEndExcluding": "6.18.53"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1", "versionEndExcluding": "7.2.7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.1", "versionEndExcluding": "7.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.265"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.216"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.183"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.148"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0.10"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/cebda2a2bb4183550eae9dcf888c16407b4fffda"}, {"url": "https://git.kernel.org/stable/c/3484a99303912db62428494a9061212049027e57"}, {"url": "https://git.kernel.org/stable/c/bc489c0c9b8c86bd7fac42cfd1bb152f042fca56"}, {"url": "https://git.kernel.org/stable/c/e7d28823c662128caae63f14e16bd394916c139b"}], "title": "bpf: Reject legacy packet loads from callbacks", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/bpf/verifier.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "cebda2a2bb4183550eae9dcf888c16407b4fffda", "status": "affected", "version": "8674e2db06cff6b50f2216eed9a761d15425bb34", "versionType": "git"}, {"lessThan": "3484a99303912db62428494a9061212049027e57", "status": "affected", "version": "ce01a4e5cfac7adbe0be565f90cd32ecbb2f8337", "versionType": "git"}, {"lessThan": "bc489c0c9b8c86bd7fac42cfd1bb152f042fca56", "status": "affected", "version": "ee861486e377edc55361c08dcbceab3f6b6577bd", "versionType": "git"}, {"lessThan": "e7d28823c662128caae63f14e16bd394916c139b", "status": "affected", "version": "ee861486e377edc55361c08dcbceab3f6b6577bd", "versionType": "git"}, {"status": "affected", "version": "928d354ae3557e8f755a227e67be88034eb3cd7f", "versionType": "git"}, {"status": "affected", "version": "8a800497d9f6c2ec9c2c1ba7b71d0ac2ea7f7bbe", "versionType": "git"}, {"status": "affected", "version": "de1055e7f9e67af32b1f3376066272b04e5223c0", "versionType": "git"}, {"status": "affected", "version": "37ad2bb11e9de92cb7b94548705eeedd87f7d392", "versionType": "git"}, {"status": "affected", "version": "d846d83bdacbd8f14fc45c63b8c1d22608452e1c", "versionType": "git"}, {"lessThan": "6.12.114", "status": "affected", "version": "6.12.101", "versionType": "semver"}, {"lessThan": "6.18.53", "status": "affected", "version": "6.18.42", "versionType": "semver"}, {"lessThan": "5.11", "status": "affected", "version": "5.10.265", "versionType": "semver"}, {"lessThan": "5.16", "status": "affected", "version": "5.15.216", "versionType": "semver"}, {"lessThan": "6.2", "status": "affected", "version": "6.1.183", "versionType": "semver"}, {"lessThan": "6.7", "status": "affected", "version": "6.6.148", "versionType": "semver"}, {"lessThan": "7.1", "status": "affected", "version": "7.0.10", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/bpf/verifier.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.1"}, {"lessThan": "7.1", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.53", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.7", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject legacy packet loads from callbacks\n\ncheck_ld_abs() models a failed BPF_LD_ABS or BPF_LD_IND in a\nsubprogram as an implicit return with R0 set to zero. It calls\nprepare_func_exit() to explore this synthesized path.\n\nWhen the load is reached directly from a synchronous callback,\nprepare_func_exit() enforces the callback return contract and marks R0\nprecise. R0 is not derived from a real instruction on this path, so\nprecision backtracking reaches the callback call with R0 still requested\nand triggers the \"callback unexpected regs\" verifier bug. A privileged\nprogram loader can therefore cause a verifier warning and an -EFAULT\nBPF_PROG_LOAD.\n\nThese legacy packet-load instructions are deprecated. Reject them from\ncallbacks rather than complicating their implicit-return model. Check all\nactive frames before constructing the implicit return so nested static\nsubprograms cannot hide the callback context.\n\nGlobal functions are verified independently with a fresh frame zero, so\nan active-frame check cannot identify a global function called from a\ncallback. Also check the complete subprogram call graph during stack-depth\nvalidation and reject a function containing a legacy load when any caller\nis a callback. This covers global and static descendants without making\nhas_ld_abs transitive, preserving its per-function BTF return-type check.\nOrdinary uses outside callbacks remain supported."}], "id": "CVE-2026-98044", "lastModified": "2026-10-21T13:21:20.053", "metrics": {}, "published": "2026-09-25T11:17:33.200", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3484a99303912db62428494a9061212049027e57"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/bc489c0c9b8c86bd7fac42cfd1bb152f042fca56"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/cebda2a2bb4183550eae9dcf888c16407b4fffda"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e7d28823c662128caae63f14e16bd394916c139b"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: bpf: Reject legacy packet loads from callbacks", "id": "2541196", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2541196"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-617", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbpf: Reject legacy packet loads from callbacks\ncheck_ld_abs() models a failed BPF_LD_ABS or BPF_LD_IND in a\nsubprogram as an implicit return with R0 set to zero. It calls\nprepare_func_exit() to explore this synthesized path.\nWhen the load is reached directly from a synchronous callback,\nprepare_func_exit() enforces the callback return contract and marks R0\nprecise. R0 is not derived from a real instruction on this path, so\nprecision backtracking reaches the callback call with R0 still requested\nand triggers the \"callback unexpected regs\" verifier bug. A privileged\nprogram loader can therefore cause a verifier warning and an -EFAULT\nBPF_PROG_LOAD.\nThese legacy packet-load instructions are deprecated. Reject them from\ncallbacks rather than complicating their implicit-return model. Check all\nactive frames before constructing the implicit return so nested static\nsubprograms cannot hide the callback context.\nGlobal functions are verified independently with a fresh frame zero, so\nan active-frame check cannot identify a global function called from a\ncallback. Also check the complete subprogram call graph during stack-depth\nvalidation and reject a function containing a legacy load when any caller\nis a callback. This covers global and static descendants without making\nhas_ld_abs transitive, preserving its per-function BTF return-type check.\nOrdinary uses outside callbacks remain supported.", "A flaw was found in the Linux kernel's BPF (Berkeley Packet Filter) verifier. This issue allows a privileged local user to cause a Denial of Service (DoS) or unexpected program rejection by loading a specially crafted BPF program containing legacy packet-load instructions inside callback functions. Due to an internal logic error during register state analysis on simulated return paths, the verifier fails validation and triggers a kernel warning."], "name": "CVE-2026-98044", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98044\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98044\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98044.mbox"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ce01a4e5cfac7adbe0be565f90cd32ecbb2f8337,3484a99303912db62428494a9061212049027e57)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ee861486e377edc55361c08dcbceab3f6b6577bd,bc489c0c9b8c86bd7fac42cfd1bb152f042fca56)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ee861486e377edc55361c08dcbceab3f6b6577bd,e7d28823c662128caae63f14e16bd394916c139b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "928d354ae3557e8f755a227e67be88034eb3cd7f"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "8a800497d9f6c2ec9c2c1ba7b71d0ac2ea7f7bbe"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "de1055e7f9e67af32b1f3376066272b04e5223c0"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "37ad2bb11e9de92cb7b94548705eeedd87f7d392"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "8674e2db06cff6b50f2216eed9a761d15425bb34"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "d846d83bdacbd8f14fc45c63b8c1d22608452e1c"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.18.42,6.18.53)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[5.10.265,5.11)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[5.15.216,5.16)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.1.183,6.2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.6.148,6.7)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.12.101,6.13)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[7.0.10,7.1)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "7.1"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,7.1)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.53,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2.7,7.2.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc2,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-25T18:15:16.265829+00:00", "updated": "2026-09-30T14:00:07.502678+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}