{
  "threat_severity" : "Moderate",
  "public_date" : "2025-02-27T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: padata: fix UAF in padata_reorder",
    "id" : "2348516",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2348516"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.0",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-820",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\npadata: fix UAF in padata_reorder\nA bug was found when run ltp test:\nBUG: KASAN: slab-use-after-free in padata_find_next+0x29/0x1a0\nRead of size 4 at addr ffff88bbfe003524 by task kworker/u113:2/3039206\nCPU: 0 PID: 3039206 Comm: kworker/u113:2 Kdump: loaded Not tainted 6.6.0+\nWorkqueue: pdecrypt_parallel padata_parallel_worker\nCall Trace:\n<TASK>\ndump_stack_lvl+0x32/0x50\nprint_address_description.constprop.0+0x6b/0x3d0\nprint_report+0xdd/0x2c0\nkasan_report+0xa5/0xd0\npadata_find_next+0x29/0x1a0\npadata_reorder+0x131/0x220\npadata_parallel_worker+0x3d/0xc0\nprocess_one_work+0x2ec/0x5a0\nIf 'mdelay(10)' is added before calling 'padata_find_next' in the\n'padata_reorder' function, this issue could be reproduced easily with\nltp test (pcrypt_aead01).\nThis can be explained as bellow:\npcrypt_aead_encrypt\n...\npadata_do_parallel\nrefcount_inc(&pd->refcnt); // add refcnt\n...\npadata_do_serial\npadata_reorder // pd\nwhile (1) {\npadata_find_next(pd, true); // using pd\nqueue_work_on\n...\npadata_serial_workercrypto_del_alg\npadata_put_pd_cnt // sub refcnt\npadata_free_shell\npadata_put_pd(ps->pd);\n// pd is freed\n// loop again, but pd is freed\n// call padata_find_next, UAF\n}\nIn the padata_reorder function, when it loops in 'while', if the alg is\ndeleted, the refcnt may be decreased to 0 before entering\n'padata_find_next', which leads to UAF.\nAs mentioned in [1], do_serial is supposed to be called with BHs disabled\nand always happen under RCU protection, to address this issue, add\nsynchronize_rcu() in 'padata_free_shell' wait for all _do_serial calls\nto finish.\n[1] https://lore.kernel.org/all/20221028160401.cccypv4euxikusiq@parnassus.localdomain/\n[2] https://lore.kernel.org/linux-kernel/jfjz5d7zwbytztackem7ibzalm5lnxldi2eofeiczqmqs2m7o6@fq426cwnjtkm/", "A use-after-free vulnerability was found in the Linux kernel's padata subsystem, in the `padata_reorder()` function. Caused by improper synchronization controls, this vulnerability can occur when a reference-counted data structure (`pd`) is decremented in one thread, freeing it, while another thread still holds a pointer to it and attempts to access it via `padata_find_next()`. This vulnerability can lead to system instability, denial of service, and potential privilege escalation." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2025-08-04T00:00:00Z",
    "advisory" : "RHSA-2025:12662",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.0",
    "package" : "kernel-0:6.12.0-55.25.1.el10_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20095",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.1",
    "package" : "kernel-0:6.12.0-124.8.1.el10_1"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2025-08-11T00:00:00Z",
    "advisory" : "RHSA-2025:13590",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.69.1.rt7.410.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2020-11-04T00:00:00Z",
    "advisory" : "RHSA-2020:4431",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-240.el8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2025-08-11T00:00:00Z",
    "advisory" : "RHSA-2025:13589",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.69.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
    "release_date" : "2025-09-02T00:00:00Z",
    "advisory" : "RHSA-2025:15035",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.4",
    "package" : "kernel-0:4.18.0-305.170.1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
    "release_date" : "2025-09-02T00:00:00Z",
    "advisory" : "RHSA-2025:15035",
    "cpe" : "cpe:/o:redhat:rhel_eus_long_life:8.4",
    "package" : "kernel-0:4.18.0-305.170.1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
    "release_date" : "2025-08-13T00:00:00Z",
    "advisory" : "RHSA-2025:13776",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.6",
    "package" : "kernel-0:4.18.0-372.157.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Telecommunications Update Service",
    "release_date" : "2025-08-13T00:00:00Z",
    "advisory" : "RHSA-2025:13776",
    "cpe" : "cpe:/o:redhat:rhel_tus:8.6",
    "package" : "kernel-0:4.18.0-372.157.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions",
    "release_date" : "2025-08-13T00:00:00Z",
    "advisory" : "RHSA-2025:13776",
    "cpe" : "cpe:/o:redhat:rhel_e4s:8.6",
    "package" : "kernel-0:4.18.0-372.157.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
    "release_date" : "2025-08-05T00:00:00Z",
    "advisory" : "RHSA-2025:13061",
    "cpe" : "cpe:/o:redhat:rhel_tus:8.8",
    "package" : "kernel-0:4.18.0-477.104.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
    "release_date" : "2025-08-05T00:00:00Z",
    "advisory" : "RHSA-2025:13061",
    "cpe" : "cpe:/o:redhat:rhel_e4s:8.8",
    "package" : "kernel-0:4.18.0-477.104.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-08-04T00:00:00Z",
    "advisory" : "RHSA-2025:12746",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-570.32.1.el9_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20518",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.5.1.el9_7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-08-04T00:00:00Z",
    "advisory" : "RHSA-2025:12746",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-570.32.1.el9_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2025-11-11T00:00:00Z",
    "advisory" : "RHSA-2025:20518",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-611.5.1.el9_7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions",
    "release_date" : "2025-08-19T00:00:00Z",
    "advisory" : "RHSA-2025:14054",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.0",
    "package" : "kernel-0:5.14.0-70.142.1.el9_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions",
    "release_date" : "2025-08-19T00:00:00Z",
    "advisory" : "RHSA-2025:14094",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.0::nfv",
    "package" : "kernel-rt-0:5.14.0-70.142.1.rt21.214.el9_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
    "release_date" : "2025-08-13T00:00:00Z",
    "advisory" : "RHSA-2025:13781",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.2",
    "package" : "kernel-0:5.14.0-284.130.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
    "release_date" : "2025-08-11T00:00:00Z",
    "advisory" : "RHSA-2025:13633",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.2::nfv",
    "package" : "kernel-rt-0:5.14.0-284.130.1.rt14.415.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.4 Extended Update Support",
    "release_date" : "2025-08-06T00:00:00Z",
    "advisory" : "RHSA-2025:13135",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.4",
    "package" : "kernel-0:5.14.0-427.81.1.el9_4"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2025-21727\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21727\nhttps://lore.kernel.org/linux-cve-announce/2025022648-CVE-2025-21727-b034@gregkh/T" ],
  "name" : "CVE-2025-21727",
  "csaw" : false
}