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{"bugzilla": {"description": "kernel: netfilter: nf_conntrack_expect: skip expectations in other netns via proc", "id": "2460701", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2460701"}, "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-653", "details": ["A flaw was found in the Linux kernel's netfilter subsystem. This vulnerability allows a local user to potentially access or view network connection tracking expectations (`nf_conntrack_expect`) from other network namespaces (`netns`) via the `/proc` filesystem. This could lead to information disclosure or a bypass of network isolation, compromising the intended separation between different network environments."], "name": "CVE-2026-31496", "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": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-22T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31496\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31496\nhttps://lore.kernel.org/linux-cve-announce/2026042203-CVE-2026-31496-e130@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b03f38d0487f3908696242286d934c9b38f9d2a,2028405ea6987b4448784e439413202cfe19f43f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b03f38d0487f3908696242286d934c9b38f9d2a,168145c87444619e3e649322bbe7719ecd00d411)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b03f38d0487f3908696242286d934c9b38f9d2a,dcfcd95b3ae7683e8ae55c92284b3430ce614bc7)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b03f38d0487f3908696242286d934c9b38f9d2a,9ca8c7452493d915f9bbf2f39331e6c583d07a23)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b03f38d0487f3908696242286d934c9b38f9d2a,3265ad619987cb551edaf797ed056d80ac450225)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b03f38d0487f3908696242286d934c9b38f9d2a,3db5647984de03d9cae0dcddb509b058351f0ee4)"}}], "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": "semver", "value": "2.6.28"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,2.6.28)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.168,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.131,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.80,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.21,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.11,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0,*]"}}], "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"}], "analysis": {"en": {"generated_at": "2026-04-29T00:04:32.378535+00:00", "value": {"mitigation_remediation": ["Apply the latest Linux kernel update that contains the nf_conntrack_expect patch", "If a kernel update cannot be applied immediately, unload the nf_conntrack_expect module so that its /proc entries are no longer exposed", "Limit read access to the /proc netfilter directory by ensuring that only privileged or trusted users can read the files and by tightening policies that govern network-namespace administration"], "summary": {"action": "Update Kernel", "impact": "Information Disclosure via /proc of other network namespaces"}, "threat_synthesis": {"affected_systems": "The flaw is present in the Linux kernel\u2019s nf_conntrack_expect component across many releases, as indicated by the CPE strings covering all modern kernel versions including 2.6.28 and the 7.0 release candidates. Any Linux system running a kernel that includes this module and has /proc exposed to local users is at risk. The CNA indicates the vendor as Linux:Linux, implying all distributions that ship the default kernel are affected unless the kernel is patched or the module is disabled.", "description_and_impact": "The nf_conntrack_expect subsystem in the Linux kernel has a logic flaw that allows any process with read access to the /proc filesystem to enumerate expectations that belong to another network namespace. This results in the exposure of state about cross-namespace connections, revealing sensitive traffic patterns and potentially allowing an attacker to infer the presence of devices or services in another namespace. The vulnerability is a moderate-severity kernel data-exposure flaw with a CVSS score of 5.5.", "risk_and_exploitability": "The EPSS score is reported as less than 1% and the vulnerability is not listed in the CISA KEV catalog, suggesting low exploitation activity. The attack vector is local \u2013 an adversary must be able to read /proc entries, which typically requires the same privileges as the kernel process or a user granted read access to /proc. The CVSS base score of 5.5 reflects the moderate impact with limited scope. No remote or privilege-escalation vector is documented; the flaw is strictly an information-disclosure problem with local read access as the prerequisite."}}}}, "created": "2026-04-22T17:30:22.456260+00:00", "updated": "2026-04-29T00:15:43.460558+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}