CVE-2016-2167
Status: ModifiedMedium (6.8)—
The canonicalize_username function in svnserve/cyrus_auth.c in Apache Subversion before 1.8.16 and 1.9.x before 1.9.4, when Cyrus SASL authentication is used, allows remote attackers to authenticate and bypass intended access restrictions via a realm string that is a prefix of an expected repository realm string.
CVSS
- Version: 3.0
- Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
- Base score: 6.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 6.81%
- Percentile among all scored CVEs: 94
- Score date: 10/5/2026
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-284
References
- http://lists.fedoraproject.org/pipermail/package-announce/2016-May/184545.html
- http://lists.opensuse.org/opensuse-updates/2016-05/msg00043.html
- http://lists.opensuse.org/opensuse-updates/2016-05/msg00044.html
- http://mail-archives.apache.org/mod_mbox/subversion-announce/201604.mbox/%3CCAP_GPNgJet+7_MAhomFVOXPgLtewcUw9w=k9zdPCkq5tvPxVMA%40mail.gmail.com%3E
- http://mail-archives.apache.org/mod_mbox/subversion-announce/201604.mbox/%3CCAP_GPNgfn1iKueW51EpmXzXi_URNfGNofZSgOyW1_jnSeNm5DQ%40mail.gmail.com%3E
- http://subversion.apache.org/security/CVE-2016-2167-advisory.txt
- http://www.debian.org/security/2016/dsa-3561
- http://www.securityfocus.com/bid/89417
- http://www.securitytracker.com/id/1035706
- http://www.slackware.com/security/viewer.php?l=slackware-security&y=2016&m=slackware-security.417496
- https://security.gentoo.org/glsa/201610-05
- https://www.oracle.com/security-alerts/cpuoct2020.html
- http://lists.fedoraproject.org/pipermail/package-announce/2016-May/184545.html
- http://lists.opensuse.org/opensuse-updates/2016-05/msg00043.html
- http://lists.opensuse.org/opensuse-updates/2016-05/msg00044.html
- http://mail-archives.apache.org/mod_mbox/subversion-announce/201604.mbox/%3CCAP_GPNgJet+7_MAhomFVOXPgLtewcUw9w=k9zdPCkq5tvPxVMA%40mail.gmail.com%3E
- http://mail-archives.apache.org/mod_mbox/subversion-announce/201604.mbox/%3CCAP_GPNgfn1iKueW51EpmXzXi_URNfGNofZSgOyW1_jnSeNm5DQ%40mail.gmail.com%3E
- http://subversion.apache.org/security/CVE-2016-2167-advisory.txt
- http://www.debian.org/security/2016/dsa-3561
- http://www.securityfocus.com/bid/89417
- http://www.securitytracker.com/id/1035706
- http://www.slackware.com/security/viewer.php?l=slackware-security&y=2016&m=slackware-security.417496
- https://security.gentoo.org/glsa/201610-05
- https://www.oracle.com/security-alerts/cpuoct2020.html
Raw JSON (NVD)
Show
{
"id": "CVE-2016-2167",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 4.9,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:S/C:P/I:P/A:N",
"authentication": "SINGLE",
"integrityImpact": "PARTIAL",
"accessComplexity": "MEDIUM",
"availabilityImpact": "NONE",
"confidentialityImpact": "PARTIAL"
},
"acInsufInfo": false,
"impactScore": 4.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 6.8,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV30": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.0",
"baseScore": 6.8,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "NONE",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 1.6
}
]
},
"affected": [
{
"source": "secalert@redhat.com",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2016-05-05T18:59:00.117",
"references": [
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{
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{
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{
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"source": "af854a3a-2127-422b-91ae-364da2661108"
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{
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"tags": [
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{
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{
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"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
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{
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"source": "af854a3a-2127-422b-91ae-364da2661108"
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],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-284"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "The canonicalize_username function in svnserve/cyrus_auth.c in Apache Subversion before 1.8.16 and 1.9.x before 1.9.4, when Cyrus SASL authentication is used, allows remote attackers to authenticate and bypass intended access restrictions via a realm string that is a prefix of an expected repository realm string."
},
{
"lang": "es",
"value": "La función canonicalize_username en svnserve/cyrus_auth.c en Apache Subversion en versiones anteriores a 1.8.16 y 1.9.x en versiones anteriores a 1.9.4, cuando se utiliza autenticación Cyrus SASL, permite a atacantes remotos autenticarse y eludir restricciones destinadas al acceso a través de una cadena realm que se prefija a un repositorio de cadena realm esperado."
}
],
"lastModified": "2026-06-17T00:43:34.313",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:apache:subversion:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "DD9BA15E-397D-4B1F-B755-8FFBBF58AE59",
"versionEndIncluding": "1.8.15"
},
{
"criteria": "cpe:2.3:a:apache:subversion:1.9.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "892FF423-1848-4E69-8C4C-E1972B656196"
},
{
"criteria": "cpe:2.3:a:apache:subversion:1.9.1:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9ACF37C7-8752-4A8F-B7E3-2E813C4A0DF0"
},
{
"criteria": "cpe:2.3:a:apache:subversion:1.9.2:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "74200C33-9505-48EB-964D-6CA28C7F6DB8"
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{
"criteria": "cpe:2.3:a:apache:subversion:1.9.3:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "09FBAFE7-986D-4B24-8122-FDCC380331C9"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "secalert@redhat.com"
}