CVE-2026-59099 (GCVE-0-2026-59099)
Vulnerability from cvelistv5
Published
2026-07-02 19:42
Modified
2026-07-14 22:03
Severity ?
9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
9.3 (Critical) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
9.3 (Critical) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
VLAI Severity ?
EPSS score ?
CWE
- CWE-323 - Reusing a Nonce, Key Pair in Encryption
Summary
Apereo CAS 7.3.0 before 8.0.0-RC6 contains a cryptographic vulnerability that allows remote unauthenticated attackers to recover plaintext conversation state by exploiting AES-GCM initialization vector reuse across the server lifetime. Attackers can collect multiple client-side webflow execution tokens from the unauthenticated login page and perform known-plaintext analysis to decrypt the webflow conversation state due to keystream reuse caused by a fixed all-zero IV paired with the same encryption key.
References
| URL | Tags | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|||||||||||||||||
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-59099",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-06T12:29:20.364889Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-07-06T12:30:35.548Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"packageURL": "pkg:github/apereo/cas",
"product": "cas",
"repo": "https://github.com/apereo/cas",
"vendor": "apereo",
"versions": [
{
"lessThan": "8.0.0-RC6",
"status": "affected",
"version": "7.3.0",
"versionType": "custom"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:apereo:central_authentication_service:*:*:*:*:*:*:*:*",
"versionEndExcluding": "8.0.0-RC6",
"versionStartIncluding": "7.3.0",
"vulnerable": true
}
],
"operator": "OR"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "George Chen"
}
],
"datePublic": "2026-06-18T00:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "Apereo CAS 7.3.0 before 8.0.0-RC6 contains a cryptographic vulnerability that allows remote unauthenticated attackers to recover plaintext conversation state by exploiting AES-GCM initialization vector reuse across the server lifetime. Attackers can collect multiple client-side webflow execution tokens from the unauthenticated login page and perform known-plaintext analysis to decrypt the webflow conversation state due to keystream reuse caused by a fixed all-zero IV paired with the same encryption key."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 9.1,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
},
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "NETWORK",
"baseScore": 9.3,
"baseSeverity": "CRITICAL",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-323",
"description": "Reusing a Nonce, Key Pair in Encryption",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-14T22:03:25.158Z",
"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"shortName": "VulnCheck"
},
"references": [
{
"name": "Maintainer Advisory",
"tags": [
"vendor-advisory"
],
"url": "https://apereo.github.io/2026/06/18/vuln/"
},
{
"name": "Release Notes",
"tags": [
"release-notes"
],
"url": "https://github.com/apereo/cas/releases/tag/v8.0.0-RC6"
},
{
"name": "Researcher Disclosure",
"tags": [
"technical-description",
"exploit"
],
"url": "https://github.com/geo-chen/oss/blob/main/cas.md"
},
{
"name": "Fix Commit",
"tags": [
"patch"
],
"url": "https://github.com/apereo/cas/commit/22c6f4adf738852782309b523b4e80371057f2d0"
},
{
"tags": [
"third-party-advisory"
],
"url": "https://www.vulncheck.com/advisories/apereo-cas-rc6-aes-gcm-nonce-reuse-information-disclosure"
}
],
"tags": [
"x_open-source"
],
"title": "Apereo CAS 7.3.0 \u003c 8.0.0-RC6 - AES-GCM Nonce Reuse Information Disclosure",
"x_generator": {
"engine": "vulncheck-endgame"
}
}
},
"cveMetadata": {
"assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"assignerShortName": "VulnCheck",
"cveId": "CVE-2026-59099",
"datePublished": "2026-07-02T19:42:51.897Z",
"dateReserved": "2026-07-02T15:38:18.929Z",
"dateUpdated": "2026-07-14T22:03:25.158Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-59099\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-06T12:29:20.364889Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-06T12:30:30.465Z\"}}], \"cna\": {\"tags\": [\"x_open-source\"], \"title\": \"Apereo CAS 7.3.0 \u003c 8.0.0-RC6 - AES-GCM Nonce Reuse Information Disclosure\", \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"George Chen\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 9.1, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}, {\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 9.3, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"HIGH\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"HIGH\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"repo\": \"https://github.com/apereo/cas\", \"vendor\": \"apereo\", \"product\": \"cas\", \"versions\": [{\"status\": \"affected\", \"version\": \"7.3.0\", \"lessThan\": \"8.0.0-RC6\", \"versionType\": \"custom\"}], \"packageURL\": \"pkg:github/apereo/cas\", \"defaultStatus\": \"unaffected\"}], \"datePublic\": \"2026-06-18T00:00:00.000Z\", \"references\": [{\"url\": \"https://apereo.github.io/2026/06/18/vuln/\", \"name\": \"Maintainer Advisory\", \"tags\": [\"vendor-advisory\"]}, {\"url\": \"https://github.com/apereo/cas/releases/tag/v8.0.0-RC6\", \"name\": \"Release Notes\", \"tags\": [\"release-notes\"]}, {\"url\": \"https://github.com/geo-chen/oss/blob/main/cas.md\", \"name\": \"Researcher Disclosure\", \"tags\": [\"technical-description\", \"exploit\"]}, {\"url\": \"https://github.com/apereo/cas/commit/22c6f4adf738852782309b523b4e80371057f2d0\", \"name\": \"Fix Commit\", \"tags\": [\"patch\"]}, {\"url\": \"https://www.vulncheck.com/advisories/apereo-cas-rc6-aes-gcm-nonce-reuse-information-disclosure\", \"tags\": [\"third-party-advisory\"]}], \"x_generator\": {\"engine\": \"vulncheck-endgame\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Apereo CAS 7.3.0 before 8.0.0-RC6 contains a cryptographic vulnerability that allows remote unauthenticated attackers to recover plaintext conversation state by exploiting AES-GCM initialization vector reuse across the server lifetime. Attackers can collect multiple client-side webflow execution tokens from the unauthenticated login page and perform known-plaintext analysis to decrypt the webflow conversation state due to keystream reuse caused by a fixed all-zero IV paired with the same encryption key.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-323\", \"description\": \"Reusing a Nonce, Key Pair in Encryption\"}]}], \"cpeApplicability\": [{\"nodes\": [{\"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:apereo:central_authentication_service:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"8.0.0-RC6\", \"versionStartIncluding\": \"7.3.0\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"83251b91-4cc7-4094-a5c7-464a1b83ea10\", \"shortName\": \"VulnCheck\", \"dateUpdated\": \"2026-07-14T22:03:25.158Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-59099\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-14T22:03:25.158Z\", \"dateReserved\": \"2026-07-02T15:38:18.929Z\", \"assignerOrgId\": \"83251b91-4cc7-4094-a5c7-464a1b83ea10\", \"datePublished\": \"2026-07-02T19:42:51.897Z\", \"assignerShortName\": \"VulnCheck\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…