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CVE-2026-72069

Estado: RecibidaCrítica (9.8)—

In the Linux kernel, the following vulnerability has been resolved:

locking/rt: Fix the incorrect RCU protection in rt_spin_unlock()

rt_spin_unlock() releases the RCU protection before unlocking the lock. That opens the door for the following UAF scenario:

Regular spinlocks keep preemption disabled accross the unlock operation, which provides full RCU protection, but the RT substitution fails to resemble that. Same applies for the rwlock substitution.

Move the rcu_read_unlock() invocation past the unlock operations to match the non-RT semantics.

Leer descripción completaMostrar menos

This makes it asymmetric vs. rt_xxx_lock(), but that's harmless as the caller needs to hold RCU read lock across the lock operation. The migrate_enable() call stays before the unlock operation because there is no per CPU operation in the unlock path which would require migration to be kept disabled.

Detalles técnicos trazas, registros y código del informe original
 T1					T2
 spin_lock(&p->lock);		rcu_read_lock();
 invalidate(p);			p = rcu_dereference(ptr);
 rcu_assign_pointer(ptr, NULL);	if (!p) return;
 spin_unlock(&p->lock);		spin_lock(&p->lock)
 				   lock(&lock->lock);
				   rcu_read_lock();
 kfree_rcu(p);			rcu_read_unlock();
				....
				spin_unlock(&p->lock)
				  rcu_read_unlock(); // Ends grace period
 rcu_do_batch()
   kfree(p);
			    UAF ->	  rt_mutex_cmpxchg_release(&lock->lock...)

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkFilter Network TrafficApplication Isolation and Sandboxing

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Linux — Linux KernelAI

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-72069",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 9.8,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "af28d801cd2db4cc7378554499bd4a5d84a5517e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "9d1fcd64ab81200e02b7a6db5eb1da8e244e8289",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "3cfaac77b3c32ac3940df28866de263c3f45d24c",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "1f0d56d3f1e88f20f6e46109402f8c15d59bac37",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "633cadbc0b8323f5cc140a285d2432089dbb534e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "83f9fb561c1c3917e19f95523dd933c7d30291aa",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f383b6dc96e976dfbf2721b0bf10bd96103b341",
              "lessThan": "89038cc87d80c77e7aa6f42a64b2573b74af339f",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "kernel/locking/spinlock_rt.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.15"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.15",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.15.217",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.184",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.148",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "kernel/locking/spinlock_rt.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-15T06:21:16.607",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1f0d56d3f1e88f20f6e46109402f8c15d59bac37",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/3cfaac77b3c32ac3940df28866de263c3f45d24c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/633cadbc0b8323f5cc140a285d2432089dbb534e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/83f9fb561c1c3917e19f95523dd933c7d30291aa",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/89038cc87d80c77e7aa6f42a64b2573b74af339f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9d1fcd64ab81200e02b7a6db5eb1da8e244e8289",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/af28d801cd2db4cc7378554499bd4a5d84a5517e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlocking/rt: Fix the incorrect RCU protection in rt_spin_unlock()\n\nrt_spin_unlock() releases the RCU protection before unlocking the\nlock. That opens the door for the following UAF scenario:\n\n T1\t\t\t\t\tT2\n spin_lock(&p->lock);\t\trcu_read_lock();\n invalidate(p);\t\t\tp = rcu_dereference(ptr);\n rcu_assign_pointer(ptr, NULL);\tif (!p) return;\n spin_unlock(&p->lock);\t\tspin_lock(&p->lock)\n \t\t\t\t   lock(&lock->lock);\n\t\t\t\t   rcu_read_lock();\n kfree_rcu(p);\t\t\trcu_read_unlock();\n\t\t\t\t....\n\t\t\t\tspin_unlock(&p->lock)\n\t\t\t\t  rcu_read_unlock(); // Ends grace period\n rcu_do_batch()\n   kfree(p);\n\t\t\t    UAF ->\t  rt_mutex_cmpxchg_release(&lock->lock...)\n\nRegular spinlocks keep preemption disabled accross the unlock operation,\nwhich provides full RCU protection, but the RT substitution fails to\nresemble that. Same applies for the rwlock substitution.\n\nMove the rcu_read_unlock() invocation past the unlock operations to match\nthe non-RT semantics. This makes it asymmetric vs. rt_xxx_lock(), but\nthat's harmless as the caller needs to hold RCU read lock across the lock\noperation. The migrate_enable() call stays before the unlock operation\nbecause there is no per CPU operation in the unlock path which would\nrequire migration to be kept disabled."
    }
  ],
  "lastModified": "2026-08-23T13:16:39.213",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}