{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-63824", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.014Z", "datePublished": "2026-07-19T12:02:20.406Z", "dateUpdated": "2026-08-17T04:51:32.494Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:51:32.494Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKEYS: fix overflow in keyctl_pkey_params_get_2()\n\nThe length for the internal output buffer is calculated incorrectly, which\ncan result overflow when a too small buffer is provided.\n\nFix the bug by allocating internal output with the size of the maximum\nlength of the cryptographic primitive instead of caller provided size." } ], "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 vulnerability is reachable only through the keyctl(2) syscall (KEYCTL_PKEY_ENCRYPT, KEYCTL_PKEY_DECRYPT, or KEYCTL_PKEY_SIGN); there is no network, adjacent, or physical attack path to the affected code.\nAC:L - An attacker fully controls the undersized out_len parameter and can reliably trigger the bug on demand with no races or victim-dependent state; CONFIG_ASYMMETRIC_KEY_TYPE is commonly enabled on server and desktop kernels.\nPR:L - Exploitation requires KEY_NEED_SEARCH on an asymmetric key, which any unprivileged local user can satisfy by loading their own RSA/EC key into a session keyring; no real root or init-namespace capabilities are needed.\nUI:N - Exploitation requires only attacker-initiated keyctl calls and does not depend on any victim user action such as opening a file or mounting a filesystem.\nS:U - Impact is confined to kernel heap memory corruption and privilege escalation within the same kernel security boundary; this is not a VM escape, sandbox escape, or cross-authority boundary violation.\nC:H - When out_len is smaller than the cryptographic output (including out_len=0 where kmalloc(0) yields ZERO_SIZE_PTR), asym_eds_op returns the full primitive output size and copy_to_user reads far beyond the allocated buffer, leaking adjacent kernel heap contents to userspace.\nI:H - The undersized kmalloc buffer is passed directly as the crypto output target; asymmetric operations can write up to the primitive maximum (hundreds of bytes for RSA-4096) past the allocation, enabling heap corruption and potential control-flow hijacking.\nA:H - Heap out-of-bounds read/write against kmalloc objects or writes through ZERO_SIZE_PTR can cause kernel oops, panic, or KASAN-detected corruption, satisfying high availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "security/keys/keyctl_pkey.c" ], "versions": [ { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "622ec2dcd59f21623f2a7ab773c80ceb7d555e3a", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "b1e247338bc71826a2d2def3e0874c34749df69a", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "0f3058d7d26f81df9b68a18ddbe164bdc3c5eff3", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "5966e4e2ba213ab7ad559166152eb4f1f170dd2c", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "5165f1cc727f1322456735df212d8e26ec237a8d", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "b11c1fa32667692a2c0566e10163758e786e430c", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "670fc6a311ed321522b7fff92cf0fc376b4f6e78", "status": "affected", "versionType": "git" }, { "version": "00d60fd3b93219ea854220f0fd264b86398cbc53", "lessThan": "cb481e59ea6cae3b7796ac1d7a22b6b24c3f3c0b", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "security/keys/keyctl_pkey.c" ], "versions": [ { "version": "4.20", "status": "affected" }, { "version": "0", "lessThan": "4.20", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.260", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.211", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.177", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.144", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.95", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.38", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.3", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "4.20", "versionEndExcluding": "5.10.260" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "5.15.211" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.1.177" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.6.144" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.12.95" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.18.38" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "7.1.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/622ec2dcd59f21623f2a7ab773c80ceb7d555e3a" }, { "url": "https://git.kernel.org/stable/c/b1e247338bc71826a2d2def3e0874c34749df69a" }, { "url": "https://git.kernel.org/stable/c/0f3058d7d26f81df9b68a18ddbe164bdc3c5eff3" }, { "url": "https://git.kernel.org/stable/c/5966e4e2ba213ab7ad559166152eb4f1f170dd2c" }, { "url": "https://git.kernel.org/stable/c/5165f1cc727f1322456735df212d8e26ec237a8d" }, { "url": "https://git.kernel.org/stable/c/b11c1fa32667692a2c0566e10163758e786e430c" }, { "url": "https://git.kernel.org/stable/c/670fc6a311ed321522b7fff92cf0fc376b4f6e78" }, { "url": "https://git.kernel.org/stable/c/cb481e59ea6cae3b7796ac1d7a22b6b24c3f3c0b" } ], "title": "KEYS: fix overflow in keyctl_pkey_params_get_2()", "x_generator": { "engine": "bippy-1.2.0" } } } }