FKIE_CVE-2016-4979
Vulnerability from fkie_nvd - Published: 2016-07-06 14:59 - Updated: 2026-06-17 00:48
Severity
Summary
The Apache HTTP Server 2.4.18 through 2.4.20, when mod_http2 and mod_ssl are enabled, does not properly recognize the "SSLVerifyClient require" directive for HTTP/2 request authorization, which allows remote attackers to bypass intended access restrictions by leveraging the ability to send multiple requests over a single connection and aborting a renegotiation.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| apache | http_server | 2.4.18 | |
| apache | http_server | 2.4.19 | |
| apache | http_server | 2.4.20 |
{
"affected": [
{
"affectedData": [
{
"product": "n/a",
"vendor": "n/a",
"versions": [
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"status": "affected",
"version": "n/a"
}
]
}
],
"source": "secalert@redhat.com"
}
],
"configurations": [
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"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "The Apache HTTP Server 2.4.18 through 2.4.20, when mod_http2 and mod_ssl are enabled, does not properly recognize the \"SSLVerifyClient require\" directive for HTTP/2 request authorization, which allows remote attackers to bypass intended access restrictions by leveraging the ability to send multiple requests over a single connection and aborting a renegotiation."
},
{
"lang": "es",
"value": "El servidor HTTP Apache 2.4.18 hasta la versi\u00f3n 2.4.20, cuando mod_http2 y mod_ssl est\u00e1n activados, no reconoce adecuadamente la directiva \"SSLVerifyClient require\" para autorizaci\u00f3n de petici\u00f3n HTTP/2, lo que permite a atacantes remotos eludir las restricciones destinadas al acceso aprovechando la capacidad de enviar m\u00faltiples peticiones sobre una sola conexi\u00f3n y abortar una renegociaci\u00f3n."
}
],
"id": "CVE-2016-4979",
"lastModified": "2026-06-17T00:48:33.000",
"metrics": {
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{
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"baseSeverity": "MEDIUM",
"cvssData": {
"accessComplexity": "LOW",
"accessVector": "NETWORK",
"authentication": "NONE",
"availabilityImpact": "NONE",
"baseScore": 5.0,
"confidentialityImpact": "NONE",
"integrityImpact": "PARTIAL",
"vectorString": "AV:N/AC:L/Au:N/C:N/I:P/A:N",
"version": "2.0"
},
"exploitabilityScore": 10.0,
"impactScore": 2.9,
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"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"version": "3.0"
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"published": "2016-07-06T14:59:04.487",
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"sourceIdentifier": "secalert@redhat.com",
"vulnStatus": "Modified",
"weaknesses": [
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{
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"value": "CWE-284"
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}
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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