CVE-2025-39682

{"id": "CVE-2025-39682", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-39682", "role": "CISA Coordinator", "options": [{"exploitation": "active"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-09-19T03:56:25.358027Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}]}, "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": "84c61fe1a75b4255df1e1e7c054c9e6d048da417", "lessThan": "2902c3ebcca52ca845c03182000e8d71d3a5196f", "versionType": "git"}, {"status": "affected", "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417", "lessThan": "c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677", "versionType": "git"}, {"status": "affected", "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417", "lessThan": "3439c15ae91a517cf3c650ea15a8987699416ad9", "versionType": "git"}, {"status": "affected", "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417", "lessThan": "29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e", "versionType": "git"}, {"status": "affected", "version": "84c61fe1a75b4255df1e1e7c054c9e6d048da417", "lessThan": "62708b9452f8eb77513115b17c4f8d1a22ebf843", "versionType": "git"}], "programFiles": ["net/tls/tls_sw.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.0"}, {"status": "unaffected", "version": "0", "lessThan": "6.0", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.149", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.103", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.44", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.16.4", "versionType": "semver", "lessThanOrEqual": "6.16.*"}, {"status": "unaffected", "version": "6.17", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/tls/tls_sw.c"], "defaultStatus": "affected"}]}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "affectedData": [{"vendor": "Siemens", "product": "SIMATIC CN 4100", "versions": [{"status": "affected", "version": "0", "lessThan": "V5.0", "versionType": "custom"}], "defaultStatus": "unknown"}]}], "published": "2025-09-05T18:15:44.670", "references": [{"url": "https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html", "tags": ["Third Party Advisory"], "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39682", "tags": ["US Government Resource"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-Other"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-754"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntls: fix handling of zero-length records on the rx_list\n\nEach recvmsg() call must process either\n - only contiguous DATA records (any number of them)\n - one non-DATA record\n\nIf the next record has different type than what has already been\nprocessed we break out of the main processing loop. If the record\nhas already been decrypted (which may be the case for TLS 1.3 where\nwe don't know type until decryption) we queue the pending record\nto the rx_list. Next recvmsg() will pick it up from there.\n\nQueuing the skb to rx_list after zero-copy decrypt is not possible,\nsince in that case we decrypted directly to the user space buffer,\nand we don't have an skb to queue (darg.skb points to the ciphertext\nskb for access to metadata like length).\n\nOnly data records are allowed zero-copy, and we break the processing\nloop after each non-data record. So we should never zero-copy and\nthen find out that the record type has changed. The corner case\nwe missed is when the initial record comes from rx_list, and it's\nzero length."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ntls: soluciona el manejo de registros de longitud cero en la rx_list\n\nCada llamada a recvmsg() debe procesar o bien\n- solo registros DATA contiguos (cualquier n\u00famero de ellos)\n- un registro que no sea DATA\n\nSi el siguiente registro tiene un tipo diferente al que ya ha sido procesado, salimos del bucle de procesamiento principal. Si el registro ya ha sido descifrado (lo cual puede ocurrir con TLS 1.3 donde no conocemos el tipo hasta el descifrado), ponemos en cola el registro pendiente en la rx_list. La siguiente recvmsg() lo recoger\u00e1 de ah\u00ed.\n\nPoner en cola el skb en la rx_list despu\u00e9s del descifrado de copia cero no es posible, ya que en ese caso desciframos directamente al b\u00fafer del espacio de usuario, y no tenemos un skb para poner en cola (darg.skb apunta al skb del texto cifrado para acceder a metadatos como la longitud).\n\nSolo a los registros de datos se les permite la copia cero, y rompemos el bucle de procesamiento despu\u00e9s de cada registro que no sea de datos. As\u00ed que nunca deber\u00edamos hacer copia cero y luego descubrir que el tipo de registro ha cambiado. El caso excepcional que pasamos por alto es cuando el registro inicial proviene de la rx_list, y es de longitud cero."}], "lastModified": "2026-10-19T21:10:00.160", "cisaActionDue": "2026-09-21", "cisaExploitAdd": "2026-09-18", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DE30211F-1A6B-457E-B19D-D3E385550199", "versionEndExcluding": "6.1.149", "versionStartIncluding": "6.0"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F2293654-7169-49B5-8D0D-EE51EF8B8E48", "versionEndExcluding": "6.6.103", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "12351F24-1133-4775-960C-F2B47E81298B", "versionEndExcluding": "6.12.44", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "AFC28995-B8C3-4B68-8CB6-78E792B6629D", "versionEndExcluding": "6.16.4", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "AA9D4F6E-9336-4026-B485-4227C861B356", "versionEndExcluding": "5.0"}], "operator": "OR"}, {"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*", "vulnerable": false, "matchCriteriaId": "92619F5F-3679-4424-9455-3285FF1EF2F1"}], "operator": "OR"}], "operator": "AND"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA\u2019s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA\u2019s \u201cForensics Triage Requirements\u201d (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.", "cisaVulnerabilityName": "Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability"}