{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43304", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:56.000Z", "datePublished": "2026-05-08T13:11:24.264Z", "dateUpdated": "2026-08-05T12:27:09.910Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:27:09.910Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: define and enforce CEPH_MAX_KEY_LEN\n\nWhen decoding the key, verify that the key material would fit into\na fixed-size buffer in process_auth_done() and generally has a sane\nlength.\n\nThe new CEPH_MAX_KEY_LEN check replaces the existing check for a key\nwith no key material which is a) not universal since CEPH_CRYPTO_NONE\nhas to be excluded and b) doesn't provide much value since a smaller\nthan needed key is just as invalid as no key -- this has to be handled\nelsewhere anyway." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The vulnerable path is reached by TCP data received from a Ceph msgr2 peer during monitor/OSD authentication, through sock_recvmsg() to process_auth_done(). A malicious or compromised Ceph endpoint can supply the crafted AUTH_DONE payload over the network.\nAC:L - Once the attacker can act as the responding Ceph peer, the oversized decoded session key is a deterministic protocol field and no race or hard-to-control condition is required. The stack overwrite follows directly from the key length accepted before the fix.\nPR:N - The attacker needs no local privileges on the victim kernel; the code is reached during the network authentication handshake before the connection is fully established. Even though CephX payloads are cryptographic, a malicious configured/compromised peer can trigger the path remotely.\nUI:N - No interactive victim action is required once the vulnerable client connects to the Ceph peer as part of normal operation. The malicious AUTH_DONE response is processed automatically by the kernel client.\nS:U - The impact is compromise or crash of the same kernel/client security authority that contains the vulnerable libceph code. This is not a VM escape, IOMMU bypass, or other cross-scope boundary violation.\nC:H - The bug is attacker-controlled kernel stack memory corruption from copying an unchecked session key into a fixed-size stack buffer. Such memory corruption can reasonably be leveraged for sensitive kernel memory disclosure.\nI:H - The unchecked memcpy can overwrite adjacent kernel stack state with attacker-controlled key bytes. This is an out-of-bounds write with plausible control-flow or data corruption impact.\nA:H - The stack overflow can corrupt kernel execution state and cause an oops or panic. Even without full exploitation, a malicious peer can crash the client kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ceph/crypto.c", "net/ceph/crypto.h", "net/ceph/messenger_v2.c" ], "versions": [ { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "6405e8c680974bb74e2c98d5249fb52c7b12a6c6", "status": "affected", "versionType": "git" }, { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "8d745d38c88ecbed95f6b2b39857bf89f35a3244", "status": "affected", "versionType": "git" }, { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "e1dc45d97975f9db65694d234fbddf1915176e16", "status": "affected", "versionType": "git" }, { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "1b275bd49e58752efb83767a5d1aed41356c5e64", "status": "affected", "versionType": "git" }, { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "c1a0f5f1e5e7e98c36a362ec3d1fcfd9932931ed", "status": "affected", "versionType": "git" }, { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "d82467c07b03a27c3c5469b62bb3b726305a80bb", "status": "affected", "versionType": "git" }, { "version": "cd1a677cad994021b19665ed476aea63f5d54f31", "lessThan": "ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf", "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/ceph/crypto.c", "net/ceph/crypto.h", "net/ceph/messenger_v2.c" ], "versions": [ { "version": "5.11", "status": "affected" }, { "version": "0", "lessThan": "5.11", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.202", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.165", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.128", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.75", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.16", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.6", "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": "5.11", "versionEndExcluding": "5.15.202" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.1.165" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.6.128" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.12.75" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.18.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.19.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/6405e8c680974bb74e2c98d5249fb52c7b12a6c6" }, { "url": "https://git.kernel.org/stable/c/8d745d38c88ecbed95f6b2b39857bf89f35a3244" }, { "url": "https://git.kernel.org/stable/c/e1dc45d97975f9db65694d234fbddf1915176e16" }, { "url": "https://git.kernel.org/stable/c/1b275bd49e58752efb83767a5d1aed41356c5e64" }, { "url": "https://git.kernel.org/stable/c/c1a0f5f1e5e7e98c36a362ec3d1fcfd9932931ed" }, { "url": "https://git.kernel.org/stable/c/d82467c07b03a27c3c5469b62bb3b726305a80bb" }, { "url": "https://git.kernel.org/stable/c/ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf" } ], "title": "libceph: define and enforce CEPH_MAX_KEY_LEN", "x_generator": { "engine": "bippy-1.2.0" } } } }