CVE-2025-40202

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-40202", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.179Z", "datePublished": "2025-11-12T21:56:34.527Z", "dateUpdated": "2026-08-05T12:08:30.982Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:08:30.982Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipmi: Rework user message limit handling\n\nThe limit on the number of user messages had a number of issues,\nimproper counting in some cases and a use after free.\n\nRestructure how this is all done to handle more in the receive message\nallocation routine, so all refcouting and user message limit counts\nare done in that routine. It's a lot cleaner and safer."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable paths are entered through ioctls on the `/dev/ipmiN` character device (`IPMICTL_SEND_MSG`, `IPMICTL_SET_GETS_EVENTS_CMD`, `IPMICTL_REGISTER_FOR_CMD`), i.e. local access to the machine. Although BMC-originated IPMB/LAN traffic also exercises the same miscounted paths, the reliable and documented trigger is the local device interface.\nAC:L - The counting imbalance is deterministic, not a race: `ipmi_set_gets_events()` sets `msg->user` without incrementing `nr_msgs` while delivery always decrements it, so a single `IPMICTL_SET_GETS_EVENTS_CMD` that drains queued events reliably underflows the counter and defeats the allocation limit. No memory-layout or timing conditions outside the attacker's control are required.\nPR:L - Neither `ipmi_devintf.c` nor `ipmi_msghandler.c` performs any capability check \u2014 reaching the bug only requires an open file descriptor on `/dev/ipmiN`, which server, appliance and embedded/telecom deployments commonly grant to an unprivileged monitoring/management group via udev so agents such as ipmitool can run without root.\nUI:N - The attacker performs everything itself with open()/ioctl() on the IPMI device; no victim action, mount, or file-open by another user is needed.\nS:U - The corrupted state (`struct ipmi_recv_msg`, `struct ipmi_user`, the driver's static watchdog/poweroff message objects) and all consequences stay within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The fix removes a genuine use-after-free (`ipmi_free_recv_msg(msg)` followed by dereferencing `msg->user`) plus release of caller-owned message objects; a freed `ipmi_recv_msg`/`ipmi_user` that the attacker can reclaim via heap grooming yields a controlled read primitive, and IPMI messages carry BMC/management-plane data.\nI:H - The use-after-free performs an atomic decrement through a stale `msg->user` pointer \u2014 an attacker-placed replacement object turns that into an arbitrary 32-bit decrement primitive, and the double release of the watchdog/poweroff static messages corrupts driver state, both leveragable toward control-flow hijack.\nA:H - Underflowing `nr_msgs` makes the signed/unsigned comparison reject every further request with `-EBUSY`, permanently disabling IPMI management (the reported real-world failure), while simultaneously defeating the `max_msgs_per_user` guard that exists specifically to stop a rogue program exhausting kernel memory; the use-after-free additionally causes oopses."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "versions": [{"version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "lessThan": "f63723ca7d7623f9dae1990973cd158671f03c56", "status": "affected", "versionType": "git"}, {"version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "lessThan": "348121b29594d42d1635648fd3ed31dfa25351d5", "status": "affected", "versionType": "git"}, {"version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "lessThan": "53d6e403affbf6df2c859a0ea00ccfc1e72090ca", "status": "affected", "versionType": "git"}, {"version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "lessThan": "0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5", "status": "affected", "versionType": "git"}, {"version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "lessThan": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "versions": [{"version": "5.19", "status": "affected"}, {"version": "0", "lessThan": "5.19", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.157", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.113", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.54", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.17.4", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18", "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": "5.19", "versionEndExcluding": "6.1.157"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.6.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.12.54"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.17.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19", "versionEndExcluding": "6.18"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/f63723ca7d7623f9dae1990973cd158671f03c56"}, {"url": "https://git.kernel.org/stable/c/348121b29594d42d1635648fd3ed31dfa25351d5"}, {"url": "https://git.kernel.org/stable/c/53d6e403affbf6df2c859a0ea00ccfc1e72090ca"}, {"url": "https://git.kernel.org/stable/c/0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5"}, {"url": "https://git.kernel.org/stable/c/b52da4054ee0bf9ecb44996f2c83236ff50b3812"}], "title": "ipmi: Rework user message limit handling", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "f63723ca7d7623f9dae1990973cd158671f03c56", "status": "affected", "version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "versionType": "git"}, {"lessThan": "348121b29594d42d1635648fd3ed31dfa25351d5", "status": "affected", "version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "versionType": "git"}, {"lessThan": "53d6e403affbf6df2c859a0ea00ccfc1e72090ca", "status": "affected", "version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "versionType": "git"}, {"lessThan": "0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5", "status": "affected", "version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "versionType": "git"}, {"lessThan": "b52da4054ee0bf9ecb44996f2c83236ff50b3812", "status": "affected", "version": "8e76741c3d8b20dfa2d6c30fa10ff927cfd93d82", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/char/ipmi/ipmi_msghandler.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.19"}, {"lessThan": "5.19", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.157", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.113", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.54", "versionType": "semver"}, {"lessThanOrEqual": "6.17.*", "status": "unaffected", "version": "6.17.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.18", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipmi: Rework user message limit handling\n\nThe limit on the number of user messages had a number of issues,\nimproper counting in some cases and a use after free.\n\nRestructure how this is all done to handle more in the receive message\nallocation routine, so all refcouting and user message limit counts\nare done in that routine. It's a lot cleaner and safer."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nipmi: Reestructurar el manejo del l\u00edmite de mensajes de usuario\n\nEl l\u00edmite en el n\u00famero de mensajes de usuario ten\u00eda una serie de problemas, conteo incorrecto en algunos casos y un uso despu\u00e9s de liberar.\n\nReestructurar c\u00f3mo se hace todo esto para manejar m\u00e1s en la rutina de asignaci\u00f3n de mensajes de recepci\u00f3n, de modo que todo el conteo de referencias y los conteos de l\u00edmite de mensajes de usuario se realicen en esa rutina. Es mucho m\u00e1s limpio y seguro."}], "id": "CVE-2025-40202", "lastModified": "2026-10-19T21:10:00.160", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2025-11-12T22:15:47.403", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0ed73be9a2547ffb9b5c1d879ad9bfab73d920b5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/348121b29594d42d1635648fd3ed31dfa25351d5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/53d6e403affbf6df2c859a0ea00ccfc1e72090ca"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b52da4054ee0bf9ecb44996f2c83236ff50b3812"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f63723ca7d7623f9dae1990973cd158671f03c56"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "kernel: ipmi: Rework user message limit handling", "id": "2414730", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2414730"}, "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"}, "details": ["No description is available for this CVE."], "name": "CVE-2025-40202", "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": "2025-11-12T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-40202\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-40202\nhttps://lore.kernel.org/linux-cve-announce/2025111246-CVE-2025-40202-f5ad@gregkh/T"], "threat_severity": "Moderate"}

{"created": "2025-11-13T09:52:19.806817+00:00", "updated": "2025-11-13T09:52:19.806841+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}