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CVE-2023-53747 (GCVE-0-2023-53747)

Vulnerability from cvelistv5 – Published: 2025-12-08 01:19 – Updated: 2026-08-05 09:15
VLAI
Title
vc_screen: reload load of struct vc_data pointer in vcs_write() to avoid UAF
Summary
In the Linux kernel, the following vulnerability has been resolved: vc_screen: reload load of struct vc_data pointer in vcs_write() to avoid UAF After a call to console_unlock() in vcs_write() the vc_data struct can be freed by vc_port_destruct(). Because of that, the struct vc_data pointer must be reloaded in the while loop in vcs_write() after console_lock() to avoid a UAF when vcs_size() is called. Syzkaller reported a UAF in vcs_size(). BUG: KASAN: slab-use-after-free in vcs_size (drivers/tty/vt/vc_screen.c:215) Read of size 4 at addr ffff8880beab89a8 by task repro_vcs_size/4119 Call Trace: <TASK> __asan_report_load4_noabort (mm/kasan/report_generic.c:380) vcs_size (drivers/tty/vt/vc_screen.c:215) vcs_write (drivers/tty/vt/vc_screen.c:664) vfs_write (fs/read_write.c:582 fs/read_write.c:564) ... <TASK> Allocated by task 1213: kmalloc_trace (mm/slab_common.c:1064) vc_allocate (./include/linux/slab.h:559 ./include/linux/slab.h:680 drivers/tty/vt/vt.c:1078 drivers/tty/vt/vt.c:1058) con_install (drivers/tty/vt/vt.c:3334) tty_init_dev (drivers/tty/tty_io.c:1303 drivers/tty/tty_io.c:1415 drivers/tty/tty_io.c:1392) tty_open (drivers/tty/tty_io.c:2082 drivers/tty/tty_io.c:2128) chrdev_open (fs/char_dev.c:415) do_dentry_open (fs/open.c:921) vfs_open (fs/open.c:1052) ... Freed by task 4116: kfree (mm/slab_common.c:1016) vc_port_destruct (drivers/tty/vt/vt.c:1044) tty_port_destructor (drivers/tty/tty_port.c:296) tty_port_put (drivers/tty/tty_port.c:312) vt_disallocate_all (drivers/tty/vt/vt_ioctl.c:662 (discriminator 2)) vt_ioctl (drivers/tty/vt/vt_ioctl.c:903) tty_ioctl (drivers/tty/tty_io.c:2778) ... The buggy address belongs to the object at ffff8880beab8800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 424 bytes inside of freed 1024-byte region [ffff8880beab8800, ffff8880beab8c00) The buggy address belongs to the physical page: page:00000000afc77580 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xbeab8 head:00000000afc77580 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff) page_type: 0xffffffff() raw: 000fffffc0010200 ffff888100042dc0 ffffea000426de00 dead000000000002 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880beab8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880beab8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880beab8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880beab8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880beab8a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Disabling lock debugging due to kernel taint
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < 934de9a9b659785fed3e820bc0c813a460c71fea (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < 0deff678157333d775af190f84696336cdcccd6d (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < a4e3c4c65ae8510e01352c9a4347e05c035b2ce2 (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < 11dddfbb7a4e62489b01074d6c04d9d1b42e4047 (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < e3d1adcad5b73c7ed0c7edb35ab68abcaa45cf67 (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < 3338d0b9acde770ee588eead5cac32c25e7048fc (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < 1de42e7653d6714a7507ba6696151a1fa028c69f (git)
Affected: ac751efa6a0d70f2c9daef5c7e3a92270f5c2dff , < 8fb9ea65c9d1338b0d2bb0a9122dc942cdd32357 (git)
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Linux Linux Affected: 2.6.38
Unaffected: 0 , < 2.6.38 (semver)
Unaffected: 4.14.327 , ≤ 4.14.* (semver)
Unaffected: 4.19.284 , ≤ 4.19.* (semver)
Unaffected: 5.4.244 , ≤ 5.4.* (semver)
Unaffected: 5.10.181 , ≤ 5.10.* (semver)
Unaffected: 5.15.113 , ≤ 5.15.* (semver)
Unaffected: 6.1.30 , ≤ 6.1.* (semver)
Unaffected: 6.3.4 , ≤ 6.3.* (semver)
Unaffected: 6.4 , ≤ * (original_commit_for_fix)
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{
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvc_screen: reload load of struct vc_data pointer in vcs_write() to avoid UAF\n\nAfter a call to console_unlock() in vcs_write() the vc_data struct can be\nfreed by vc_port_destruct(). Because of that, the struct vc_data pointer\nmust be reloaded in the while loop in vcs_write() after console_lock() to\navoid a UAF when vcs_size() is called.\n\nSyzkaller reported a UAF in vcs_size().\n\nBUG: KASAN: slab-use-after-free in vcs_size (drivers/tty/vt/vc_screen.c:215)\nRead of size 4 at addr ffff8880beab89a8 by task repro_vcs_size/4119\n\nCall Trace:\n \u003cTASK\u003e\n__asan_report_load4_noabort (mm/kasan/report_generic.c:380)\nvcs_size (drivers/tty/vt/vc_screen.c:215)\nvcs_write (drivers/tty/vt/vc_screen.c:664)\nvfs_write (fs/read_write.c:582 fs/read_write.c:564)\n...\n \u003cTASK\u003e\n\nAllocated by task 1213:\nkmalloc_trace (mm/slab_common.c:1064)\nvc_allocate (./include/linux/slab.h:559 ./include/linux/slab.h:680\n    drivers/tty/vt/vt.c:1078 drivers/tty/vt/vt.c:1058)\ncon_install (drivers/tty/vt/vt.c:3334)\ntty_init_dev (drivers/tty/tty_io.c:1303 drivers/tty/tty_io.c:1415\n    drivers/tty/tty_io.c:1392)\ntty_open (drivers/tty/tty_io.c:2082 drivers/tty/tty_io.c:2128)\nchrdev_open (fs/char_dev.c:415)\ndo_dentry_open (fs/open.c:921)\nvfs_open (fs/open.c:1052)\n...\n\nFreed by task 4116:\nkfree (mm/slab_common.c:1016)\nvc_port_destruct (drivers/tty/vt/vt.c:1044)\ntty_port_destructor (drivers/tty/tty_port.c:296)\ntty_port_put (drivers/tty/tty_port.c:312)\nvt_disallocate_all (drivers/tty/vt/vt_ioctl.c:662 (discriminator 2))\nvt_ioctl (drivers/tty/vt/vt_ioctl.c:903)\ntty_ioctl (drivers/tty/tty_io.c:2778)\n...\n\nThe buggy address belongs to the object at ffff8880beab8800\n which belongs to the cache kmalloc-1k of size 1024\nThe buggy address is located 424 bytes inside of\n freed 1024-byte region [ffff8880beab8800, ffff8880beab8c00)\n\nThe buggy address belongs to the physical page:\npage:00000000afc77580 refcount:1 mapcount:0 mapping:0000000000000000\n    index:0x0 pfn:0xbeab8\nhead:00000000afc77580 order:3 entire_mapcount:0 nr_pages_mapped:0\n    pincount:0\nflags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff)\npage_type: 0xffffffff()\nraw: 000fffffc0010200 ffff888100042dc0 ffffea000426de00 dead000000000002\nraw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000\npage dumped because: kasan: bad access detected\n\nMemory state around the buggy address:\n ffff8880beab8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n ffff8880beab8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n\u003effff8880beab8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n                                  ^\n ffff8880beab8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n ffff8880beab8a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n==================================================================\nDisabling lock debugging due to kernel taint"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - Exploitation requires local access to character device nodes \u2014 write(2) on /dev/vcsN or /dev/vcsaN and an ioctl on a VT tty for VT_DISALLOCATE. There is no network or remote-peer reachability.\nAC:L - The attacker controls both sides of the race: one thread drives the write loop (which unconditionally drops console_lock every PAGE_SIZE chunk) while another calls VT_DISALLOCATE, and the window can be stretched indefinitely by backing the user buffer with userfaultfd or FUSE so copy_from_user stalls on demand. This makes the free-and-respray step reliable rather than opportunistic.\nPR:L - VT_DISALLOCATE carries no perm or capable() check whatsoever in vt_ioctl, so the only gate is DAC on /dev/vcs* and a VT fd \u2014 held by any tty-group member, any console-logged-in user via logind ACLs, or non-root console services on embedded systems. No capability or root privilege in the initial namespace is needed.\nUI:N - The attacker performs every step \u2014 allocating the VT, opening /dev/vcs*, issuing the write and the deallocation ioctl \u2014 from its own threads. No victim action is involved.\nS:U - The use-after-free corrupts kernel heap memory within the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The stale vc_data is read after free (vcs_size, screenpos, vc_sw), and since the attacker can reclaim the kmalloc-1k slot with controlled data and set vc-\u003evc_origin arbitrarily, the write path\u0027s read-modify-write sequences (vcs_scr_readw on the computed pointer) yield an arbitrary kernel-memory read primitive.\nI:H - vcs_write_buf derives its destination pointer from the freed object\u0027s vc_origin/vc_visible_origin and then writes attacker-supplied 16-bit values there, giving a controlled arbitrary kernel write; the viewed path additionally makes an indirect call through vc-\u003evc_sw-\u003econ_screen_pos read out of freed memory, a direct control-flow hijack primitive leading to privilege escalation.\nA:H - Even unweaponized the bug is a slab use-after-free that reads and writes through a dangling pointer, producing KASAN splats, oopses, and kernel panics as syzkaller demonstrated, and it can be retriggered at will."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:15:45.787Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/934de9a9b659785fed3e820bc0c813a460c71fea"
        },
        {
          "url": "https://git.kernel.org/stable/c/0deff678157333d775af190f84696336cdcccd6d"
        },
        {
          "url": "https://git.kernel.org/stable/c/a4e3c4c65ae8510e01352c9a4347e05c035b2ce2"
        },
        {
          "url": "https://git.kernel.org/stable/c/11dddfbb7a4e62489b01074d6c04d9d1b42e4047"
        },
        {
          "url": "https://git.kernel.org/stable/c/e3d1adcad5b73c7ed0c7edb35ab68abcaa45cf67"
        },
        {
          "url": "https://git.kernel.org/stable/c/3338d0b9acde770ee588eead5cac32c25e7048fc"
        },
        {
          "url": "https://git.kernel.org/stable/c/1de42e7653d6714a7507ba6696151a1fa028c69f"
        },
        {
          "url": "https://git.kernel.org/stable/c/8fb9ea65c9d1338b0d2bb0a9122dc942cdd32357"
        }
      ],
      "title": "vc_screen: reload load of struct vc_data pointer in vcs_write() to avoid UAF",
      "x_generator": {
        "engine": "bippy-1.2.0"
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    }
  },
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    "assignerShortName": "Linux",
    "cveId": "CVE-2023-53747",
    "datePublished": "2025-12-08T01:19:06.255Z",
    "dateReserved": "2025-12-08T01:18:04.279Z",
    "dateUpdated": "2026-08-05T09:15:45.787Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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      "date": "2026-09-20",
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      "percentile": "0.03654"
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                    "lessThanOrEqual": "4.14.*",
                    "status": "unaffected",
                    "version": "4.14.327",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "4.19.*",
                    "status": "unaffected",
                    "version": "4.19.284",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.4.*",
                    "status": "unaffected",
                    "version": "5.4.244",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.10.*",
                    "status": "unaffected",
                    "version": "5.10.181",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "5.15.*",
                    "status": "unaffected",
                    "version": "5.15.113",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.1.*",
                    "status": "unaffected",
                    "version": "6.1.30",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.3.*",
                    "status": "unaffected",
                    "version": "6.3.4",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.4",
                    "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\nvc_screen: reload load of struct vc_data pointer in vcs_write() to avoid UAF\n\nAfter a call to console_unlock() in vcs_write() the vc_data struct can be\nfreed by vc_port_destruct(). Because of that, the struct vc_data pointer\nmust be reloaded in the while loop in vcs_write() after console_lock() to\navoid a UAF when vcs_size() is called.\n\nSyzkaller reported a UAF in vcs_size().\n\nBUG: KASAN: slab-use-after-free in vcs_size (drivers/tty/vt/vc_screen.c:215)\nRead of size 4 at addr ffff8880beab89a8 by task repro_vcs_size/4119\n\nCall Trace:\n \u003cTASK\u003e\n__asan_report_load4_noabort (mm/kasan/report_generic.c:380)\nvcs_size (drivers/tty/vt/vc_screen.c:215)\nvcs_write (drivers/tty/vt/vc_screen.c:664)\nvfs_write (fs/read_write.c:582 fs/read_write.c:564)\n...\n \u003cTASK\u003e\n\nAllocated by task 1213:\nkmalloc_trace (mm/slab_common.c:1064)\nvc_allocate (./include/linux/slab.h:559 ./include/linux/slab.h:680\n    drivers/tty/vt/vt.c:1078 drivers/tty/vt/vt.c:1058)\ncon_install (drivers/tty/vt/vt.c:3334)\ntty_init_dev (drivers/tty/tty_io.c:1303 drivers/tty/tty_io.c:1415\n    drivers/tty/tty_io.c:1392)\ntty_open (drivers/tty/tty_io.c:2082 drivers/tty/tty_io.c:2128)\nchrdev_open (fs/char_dev.c:415)\ndo_dentry_open (fs/open.c:921)\nvfs_open (fs/open.c:1052)\n...\n\nFreed by task 4116:\nkfree (mm/slab_common.c:1016)\nvc_port_destruct (drivers/tty/vt/vt.c:1044)\ntty_port_destructor (drivers/tty/tty_port.c:296)\ntty_port_put (drivers/tty/tty_port.c:312)\nvt_disallocate_all (drivers/tty/vt/vt_ioctl.c:662 (discriminator 2))\nvt_ioctl (drivers/tty/vt/vt_ioctl.c:903)\ntty_ioctl (drivers/tty/tty_io.c:2778)\n...\n\nThe buggy address belongs to the object at ffff8880beab8800\n which belongs to the cache kmalloc-1k of size 1024\nThe buggy address is located 424 bytes inside of\n freed 1024-byte region [ffff8880beab8800, ffff8880beab8c00)\n\nThe buggy address belongs to the physical page:\npage:00000000afc77580 refcount:1 mapcount:0 mapping:0000000000000000\n    index:0x0 pfn:0xbeab8\nhead:00000000afc77580 order:3 entire_mapcount:0 nr_pages_mapped:0\n    pincount:0\nflags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff)\npage_type: 0xffffffff()\nraw: 000fffffc0010200 ffff888100042dc0 ffffea000426de00 dead000000000002\nraw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000\npage dumped because: kasan: bad access detected\n\nMemory state around the buggy address:\n ffff8880beab8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n ffff8880beab8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n\u003effff8880beab8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n                                  ^\n ffff8880beab8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n ffff8880beab8a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb\n==================================================================\nDisabling lock debugging due to kernel taint"
          }
        ],
        "id": "CVE-2023-53747",
        "lastModified": "2026-08-04T10:19:19.547",
        "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": "2025-12-08T02:15:50.057",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/0deff678157333d775af190f84696336cdcccd6d"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/11dddfbb7a4e62489b01074d6c04d9d1b42e4047"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/1de42e7653d6714a7507ba6696151a1fa028c69f"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/3338d0b9acde770ee588eead5cac32c25e7048fc"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/8fb9ea65c9d1338b0d2bb0a9122dc942cdd32357"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/934de9a9b659785fed3e820bc0c813a460c71fea"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/a4e3c4c65ae8510e01352c9a4347e05c035b2ce2"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/e3d1adcad5b73c7ed0c7edb35ab68abcaa45cf67"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Deferred"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-04T19:15:49+00:00",
      "cve": "CVE-2023-53747",
      "id": "CVE-2023-53747",
      "initial_release_date": "2023-01-01T00:00:00+00:00",
      "product_status:fixed": "280",
      "product_status:known_affected": "98",
      "product_status:known_not_affected": "98",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel: Denial of Service via use-after-free in vc_screen",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-53747.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T16:46:07Z",
      "cve": "CVE-2023-53747",
      "id": "CVE-2023-53747",
      "initial_release_date": "2025-12-09T00:29:24Z",
      "product_status:known_affected": "554",
      "product_status:known_not_affected": "169",
      "product_status:recommended": "233",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2023-53747",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2023-53747.json",
      "version": "28"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.