CVE-2026-31472

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31472", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.098Z", "datePublished": "2026-04-22T13:54:00.281Z", "dateUpdated": "2026-05-11T22:09:23.766Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T22:09:23.766Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: iptfs: validate inner IPv4 header length in IPTFS payload\n\nAdd validation of the inner IPv4 packet tot_len and ihl fields parsed\nfrom decrypted IPTFS payloads in __input_process_payload(). A crafted\nESP packet containing an inner IPv4 header with tot_len=0 causes an\ninfinite loop: iplen=0 leads to capturelen=min(0, remaining)=0, so the\ndata offset never advances and the while(data < tail) loop never\nterminates, spinning forever in softirq context.\n\nReject inner IPv4 packets where tot_len < ihl*4 or ihl*4 < sizeof(struct\niphdr), which catches both the tot_len=0 case and malformed ihl values.\nThe normal IP stack performs this validation in ip_rcv_core(), but IPTFS\nextracts and processes inner packets before they reach that layer."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/xfrm/xfrm_iptfs.c"], "versions": [{"version": "6c82d2433671819a550227bf65bfb6043e3d3305", "lessThan": "de6d8e8ce5187f7402c9859b443355e7120c5f09", "status": "affected", "versionType": "git"}, {"version": "6c82d2433671819a550227bf65bfb6043e3d3305", "lessThan": "3db7d4f777a00164582061ccaa99569cd85011a3", "status": "affected", "versionType": "git"}, {"version": "6c82d2433671819a550227bf65bfb6043e3d3305", "lessThan": "0d10393d5eac33cbd92f7a41fddca12c41d3cb7e", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/xfrm/xfrm_iptfs.c"], "versions": [{"version": "6.14", "status": "affected"}, {"version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.21", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.11", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "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": "6.14", "versionEndExcluding": "6.18.21"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "6.19.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/de6d8e8ce5187f7402c9859b443355e7120c5f09"}, {"url": "https://git.kernel.org/stable/c/3db7d4f777a00164582061ccaa99569cd85011a3"}, {"url": "https://git.kernel.org/stable/c/0d10393d5eac33cbd92f7a41fddca12c41d3cb7e"}], "title": "xfrm: iptfs: validate inner IPv4 header length in IPTFS payload", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/xfrm/xfrm_iptfs.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "de6d8e8ce5187f7402c9859b443355e7120c5f09", "status": "affected", "version": "6c82d2433671819a550227bf65bfb6043e3d3305", "versionType": "git"}, {"lessThan": "3db7d4f777a00164582061ccaa99569cd85011a3", "status": "affected", "version": "6c82d2433671819a550227bf65bfb6043e3d3305", "versionType": "git"}, {"lessThan": "0d10393d5eac33cbd92f7a41fddca12c41d3cb7e", "status": "affected", "version": "6c82d2433671819a550227bf65bfb6043e3d3305", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/xfrm/xfrm_iptfs.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.14"}, {"lessThan": "6.14", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.21", "versionType": "semver"}, {"lessThanOrEqual": "6.19.*", "status": "unaffected", "version": "6.19.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "8BA62FCD-8829-4508-AFE2-0C12960267CD", "versionEndExcluding": "6.18.21", "versionStartIncluding": "6.14.1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "4CA2E747-A9EC-4518-9AA2-B4247FC748B7", "versionEndExcluding": "6.19.11", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:-:*:*:*:*:*:*", "matchCriteriaId": "7DE421BA-0600-4401-A175-73CAB6A6FB4E", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: iptfs: validate inner IPv4 header length in IPTFS payload\n\nAdd validation of the inner IPv4 packet tot_len and ihl fields parsed\nfrom decrypted IPTFS payloads in __input_process_payload(). A crafted\nESP packet containing an inner IPv4 header with tot_len=0 causes an\ninfinite loop: iplen=0 leads to capturelen=min(0, remaining)=0, so the\ndata offset never advances and the while(data < tail) loop never\nterminates, spinning forever in softirq context.\n\nReject inner IPv4 packets where tot_len < ihl*4 or ihl*4 < sizeof(struct\niphdr), which catches both the tot_len=0 case and malformed ihl values.\nThe normal IP stack performs this validation in ip_rcv_core(), but IPTFS\nextracts and processes inner packets before they reach that layer."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nxfrm: iptfs: validar la longitud del encabezado IPv4 interno en la carga \u00fatil de IPTFS\n\nA\u00f1adir validaci\u00f3n de los campos tot_len e ihl del paquete IPv4 interno analizados de las cargas \u00fatiles de IPTFS descifradas en __input_process_payload(). Un paquete ESP manipulado que contiene un encabezado IPv4 interno con tot_len=0 causa un bucle infinito: iplen=0 lleva a capturelen=min(0, remaining)=0, por lo que el desplazamiento de datos nunca avanza y el bucle while(data < tail) nunca termina, girando indefinidamente en el contexto de softirq.\n\nRechazar paquetes IPv4 internos donde tot_len < ihl4 o ihl4 < sizeof(struct iphdr), lo que detecta tanto el caso de tot_len=0 como los valores ihl mal formados. La pila IP normal realiza esta validaci\u00f3n en ip_rcv_core(), pero IPTFS extrae y procesa los paquetes internos antes de que lleguen a esa capa."}], "id": "CVE-2026-31472", "lastModified": "2026-11-11T23:10:00.263", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-04-22T14:16:43.740", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0d10393d5eac33cbd92f7a41fddca12c41d3cb7e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3db7d4f777a00164582061ccaa99569cd85011a3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/de6d8e8ce5187f7402c9859b443355e7120c5f09"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-835"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: xfrm: iptfs: validate inner IPv4 header length in IPTFS payload", "id": "2460676", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2460676"}, "csaw": false, "cwe": "CWE-606", "details": ["A flaw was found in the Linux kernel, specifically within the xfrm and iptfs components. A remote attacker could exploit this vulnerability by sending a specially crafted Encapsulating Security Payload (ESP) packet. This packet, containing an inner IPv4 header with a total length (tot_len) of zero or malformed Internet Header Length (ihl) values, could trigger an infinite loop in the kernel's processing. This issue results in a Denial of Service (DoS), rendering the affected system unresponsive."], "name": "CVE-2026-31472", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "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"}], "public_date": "2026-04-22T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31472\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31472\nhttps://lore.kernel.org/linux-cve-announce/2026042255-CVE-2026-31472-396d@gregkh/T"]}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[6c82d2433671819a550227bf65bfb6043e3d3305,de6d8e8ce5187f7402c9859b443355e7120c5f09)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[6c82d2433671819a550227bf65bfb6043e3d3305,3db7d4f777a00164582061ccaa99569cd85011a3)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[6c82d2433671819a550227bf65bfb6043e3d3305,0d10393d5eac33cbd92f7a41fddca12c41d3cb7e)"}}], "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": "6.14"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.14)"}}, {"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": "generic", "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": "2026-04-29T01:50:07.628619+00:00", "value": {"mitigation_remediation": ["Apply the kernel patch that introduces validation of the inner IPv4 header tot_len and ihl fields in __input_process_payload().", "If the patch cannot be applied immediately, block or drop suspicious ESP packets at the perimeter using firewall rules or disable IPTFS if it is not required. ", "After applying the patch, monitor softirq activity and CPU usage for any residual abnormal behavior."], "summary": {"action": "Apply Patch", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "All Linux kernels that include the IPTFS implementation prior to the commit adding tot_len and ihl validation are affected. This includes every release from the upstream Linux branch until the patch is applied; the CPE list covers kernels 6.14 and all 7.0 release candidates.", "description_and_impact": "The Linux kernel\u2019s IPTFS payload handling contains missing validation of inner IPv4 packet fields parsed from decrypted ESP payloads. An attacker can craft an ESP packet that contains an inner IPv4 header with a total length of zero or a malformed header length. This causes the inner packet processor to enter an infinite loop in softirq context because the length checks allow the offset to remain zero and the loop never terminates, consuming CPU and disabling packet processing.", "risk_and_exploitability": "The likely attack vector is inferred from the description: a remote adversary can trigger the denial of service by sending the crafted packet over any interface that processes IPsec traffic. The vulnerability does not require elevated privileges and can be exploited from any network location that can reach the host. The EPSS score is below 1% and the CVE is not in the CISA KEV catalog, but the medium CVSS score of 5.5, combined with the ease of remote trigger, still represents a notable risk to availability."}}}}, "created": "2026-04-22T17:15:21.908428+00:00", "updated": "2026-04-29T02:00:27.234192+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}