{"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"}}}}