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CVE-2021-1879

Status: AnalyzedMedium (6.1)⚠ Active exploitation

This issue was addressed by improved management of object lifetimes. This issue is fixed in iOS 12.5.2, iOS 14.4.2 and iPadOS 14.4.2, watchOS 7.3.3. Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited..

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

CISA KEV — actively exploited

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

XSS universal en navegador Safari (AV:N/UI:R) permite ejecución de scripts; CWE-79 confirma inyección, explotación activa reportada.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Restrict Web-Based ContentUser TrainingExecution PreventionBehavior Prevention on EndpointDisable or Remove Feature or ProgramApplication Isolation and Sandboxing

Affected technologies (3)

Apple — IpadosApple — Iphone OSApple — Watchos

CWEs

References

Raw JSON (NVD)

Show
{
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  "cveTags": [],
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          "options": [
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              "automatable": "no"
            },
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          "version": "2.0.3",
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          "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
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    "cvssMetricV31": [
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  "published": "2021-04-02T19:15:20.770",
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      "value": "This issue was addressed by improved management of object lifetimes. This issue is fixed in iOS 12.5.2, iOS 14.4.2 and iPadOS 14.4.2, watchOS 7.3.3. Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited.."
    },
    {
      "lang": "es",
      "value": "Este problema es abordado con una administración del tiempo de vida de objetos mejorada. Este problema es corregido en iOS versión 12.5.2, iOS versión 14.4.2 y iPadOS versión 14.4.2, watchOS versión 7.3.3. El procesamiento de contenido web diseñado malicioso puede conllevar a ataques de tipo cross site scripting universales. Apple tiene conocimiento de un reporte que indica que este problema puede haber sido explotado activamente."
    }
  ],
  "lastModified": "2026-06-17T03:32:42.883",
  "cisaActionDue": "2021-11-17",
  "cisaExploitAdd": "2021-11-03",
  "configurations": [
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}