{"id":"CVE-2025-37756","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: explicitly disallow disconnect\n\nsyzbot discovered that it can disconnect a TLS socket and then\nrun into all sort of unexpected corner cases","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: explicitly disallow disconnect\n\nsyzbot discovered that it can disconnect a TLS socket and then\nrun into all sort of unexpected corner cases. I have a vague\nre…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-20"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 4.13, < 5.10.237","linux_kernel >= 5.11, < 5.15.181","linux_kernel >= 5.16, < 6.1.135","linux_kernel >= 6.2, < 6.6.88","linux_kernel >= 6.7, < 6.12.24","linux_kernel >= 6.13, < 6.13.12","linux_kernel >= 6.14, < 6.14.3","linux_kernel = 6.15","debian_linux = 11.0"],"patched":["linux_kernel 6.14.3"],"published":"2025-05-01","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:18:17.173","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-37756","references":[{"url":"https://git.kernel.org/stable/c/2bcad8fefcecdd5f005d8c550b25d703c063c34a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5071a1e606b30c0c11278d3c6620cd6a24724cf6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7bdcf5bc35ae59fc4a0fa23276e84b4d1534a3cf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8513411ec321942bd3cfed53d5bb700665c67d86","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9fcbca0f801580cbb583e9cb274e2c7fbe766ca6","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ac91c6125468be720eafde9c973994cb45b61d44","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c665bef891e8972e1d3ce5bbc0d42a373346a2c3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f3ce4d3f874ab7919edca364c147ac735f9f1d04","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"http://www.openwall.com/lists/oss-security/2026/05/07/1","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-37756.json"},{"url":"https://access.redhat.com/security/cve/CVE-2025-37756"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2363326"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-37756"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-37756"},{"url":"https://lore.kernel.org/linux-cve-announce/2025050139-CVE-2025-37756-a06e@gregkh/T"}],"tags":["nvd","csaf","vex","red-hat","cve.org","score-dispute"],"epss":0.00298,"epssPercentile":0.22304,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T21:44:56.970467Z"},"scores":{"nvd":7.8,"vendor":3.3,"cna":7.8},"ingestedAt":"2026-10-15T22:48:25.477Z","slug":"CVE-2025-37756","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: explicitly disallow disconnect\n\nsyzbot discovered that it can disconnect a TLS socket and then\nrun into all sort of unexpected corner cases. I have a vague\nrecollection of Eric pointing this out to us a long time ago.\nSupporting disconnect is really hard, for one thing if offload\nis enabled we'd need to wait for all packets to be _acked_.\nDisconnect is not commonly used, disallow it.\n\nThe immediate problem syzbot run into is the warning in the strp,\nbut that's just the easiest bug to trigger:\n\n  WARNING: CPU: 0 PID: 5834 at net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486\n  RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486\n  Call Trace:\n   <TASK>\n   tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363\n   tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043\n   inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678\n   sock_recvmsg_nosec net/socket.c:1023 [inline]\n   sock_recvmsg+0x109/0x280 net/socket.c:1045\n   __sys_recvfrom+0x202/0x380 net/socket.c:2237\n\n## Affected\n\n- `linux_kernel >= 4.13, < 5.10.237`\n- `linux_kernel >= 5.11, < 5.15.181`\n- `linux_kernel >= 5.16, < 6.1.135`\n- `linux_kernel >= 6.2, < 6.6.88`\n- `linux_kernel >= 6.7, < 6.12.24`\n- `linux_kernel >= 6.13, < 6.13.12`\n- `linux_kernel >= 6.14, < 6.14.3`\n- `linux_kernel = 6.15`\n- `debian_linux = 11.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.14.3`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-37756.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":230015,"id":"CVE-2025-37756","ts":1793124769976,"field":"cvss","old":"3.3","new":"7.8"},{"seq":230014,"id":"CVE-2025-37756","ts":1793124769976,"field":"severity","old":"low","new":"high"},{"seq":223674,"id":"CVE-2025-37756","ts":1792238363833,"field":"cvss","old":"7.8","new":"3.3"},{"seq":223673,"id":"CVE-2025-37756","ts":1792238363833,"field":"severity","old":"high","new":"low"}]}