CVE-2017-5420
Status: ModifiedMedium (6.5)—
A "javascript:" url loaded by a malicious page can obfuscate its location by blanking the URL displayed in the addressbar, allowing for an attacker to spoof an existing page without the malicious page's address being displayed correctly. This vulnerability affects Firefox < 52.
CVSS
- Version: 3.0
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- Base score: 6.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.28%
- Percentile among all scored CVEs: 69
- Score date: 10/11/2026
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).
Affected technologies (1)
CWEs
- CWE-20
References
- http://www.securityfocus.com/bid/96692
- http://www.securitytracker.com/id/1037966
- https://bugzilla.mozilla.org/show_bug.cgi?id=1284395
- https://www.mozilla.org/security/advisories/mfsa2017-05/
- http://www.securityfocus.com/bid/96692
- http://www.securitytracker.com/id/1037966
- https://bugzilla.mozilla.org/show_bug.cgi?id=1284395
- https://www.mozilla.org/security/advisories/mfsa2017-05/
Raw JSON (NVD)
Show
{
"id": "CVE-2017-5420",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
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"source": "nvd@nist.gov",
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"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "MEDIUM",
"availabilityImpact": "NONE",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
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"cvssMetricV30": [
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"integrityImpact": "HIGH",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
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},
"impactScore": 3.6,
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"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
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"version": "unspecified",
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"published": "2018-06-11T21:29:05.140",
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"value": "A \"javascript:\" url loaded by a malicious page can obfuscate its location by blanking the URL displayed in the addressbar, allowing for an attacker to spoof an existing page without the malicious page's address being displayed correctly. This vulnerability affects Firefox < 52."
},
{
"lang": "es",
"value": "Una URL \"javascript:\" cargada por una página maliciosa puede ofuscar su ubicación dejando en blanco la URL mostrada en la barra de direcciones, lo que permite que un atacante suplante una página existente sin que la dirección maliciosa de la página se muestre correctamente. La vulnerabilidad afecta a Firefox en versiones anteriores a la 52."
}
],
"lastModified": "2026-06-17T01:20:27.127",
"configurations": [
{
"nodes": [
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