CVE-2026-26199 (GCVE-0-2026-26199)
Vulnerability from cvelistv5 – Published: 2026-07-20 14:59 – Updated: 2026-07-20 18:56
VLAI
EPSS
VEX
Title
Buffer underflow in `H5Iget_name `/`H5G_get_name` if size is zero
Summary
HDF5 is a high-performance library and a file format specification that implements the HDF5 data model. If `H5Iget_name` is invoked on a group id with `0` for the size parameter, it will underflow when trying to place a null terminator in the buffer. This can occur if `H5Iget_name` is invoked in a way where `size` can be forced to zero, and there is important data before the `name` buffer.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-124 - Buffer Underwrite ('Buffer Underflow')
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/HDFGroup/hdf5/security/advisor… | x_refsource_CONFIRM |
| https://github.com/HDFGroup/hdf5/blob/develop/src… | x_refsource_MISC |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-26199",
"options": [
{
"Exploitation": "poc"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-07-20T18:56:40.908924Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-07-20T18:56:52.113Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"references": [
{
"tags": [
"exploit"
],
"url": "https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc"
}
],
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "hdf5",
"vendor": "HDFGroup",
"versions": [
{
"status": "affected",
"version": "\u003c= 1.14.6"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "HDF5 is a high-performance library and a file format specification that implements the HDF5 data model. If `H5Iget_name` is invoked on a group id with `0` for the size parameter, it will underflow when trying to place a null terminator in the buffer. This can occur if `H5Iget_name` is invoked in a way where `size` can be forced to zero, and there is important data before the `name` buffer."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 5.9,
"baseSeverity": "MEDIUM",
"privilegesRequired": "NONE",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "ACTIVE",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-124",
"description": "CWE-124: Buffer Underwrite (\u0027Buffer Underflow\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-20T14:59:35.038Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc"
},
{
"name": "https://github.com/HDFGroup/hdf5/blob/develop/src/H5Gname.c#L474",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/HDFGroup/hdf5/blob/develop/src/H5Gname.c#L474"
}
],
"source": {
"advisory": "GHSA-5c6x-jmgf-f5vc",
"discovery": "UNKNOWN"
},
"title": "Buffer underflow in `H5Iget_name `/`H5G_get_name` if size is zero"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-26199",
"datePublished": "2026-07-20T14:59:35.038Z",
"dateReserved": "2026-02-11T19:56:24.813Z",
"dateUpdated": "2026-07-20T18:56:52.113Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-26199",
"date": "2026-07-22",
"epss": "0.00282",
"percentile": "0.20362"
},
"microsoft_vex": {
"current_release_date": "2026-07-22T01:01:26.000Z",
"cve": "CVE-2026-26199",
"id": "msrc_CVE-2026-26199",
"initial_release_date": "2026-07-22T01:01:26.000Z",
"product_status:known_affected": "1",
"source": "Microsoft CSAF VEX",
"status": "final",
"title": "Buffer underflow in `H5Iget_name `/`H5G_get_name` if size is zero",
"url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-26199.json",
"version": "1"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-26199\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-07-20T16:16:57.550\",\"lastModified\":\"2026-07-20T19:17:20.487\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"HDF5 is a high-performance library and a file format specification that implements the HDF5 data model. If `H5Iget_name` is invoked on a group id with `0` for the size parameter, it will underflow when trying to place a null terminator in the buffer. This can occur if `H5Iget_name` is invoked in a way where `size` can be forced to zero, and there is important data before the `name` buffer.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"HDFGroup\",\"product\":\"hdf5\",\"versions\":[{\"version\":\"\u003c= 1.14.6\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":5.9,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"ACTIVE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-07-20T18:56:40.908924Z\",\"id\":\"CVE-2026-26199\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-124\"}]}],\"references\":[{\"url\":\"https://github.com/HDFGroup/hdf5/blob/develop/src/H5Gname.c#L474\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-07-21T06:33:33+00:00",
"cve": "CVE-2026-26199",
"id": "CVE-2026-26199",
"initial_release_date": "2026-07-20T14:59:35.038000+00:00",
"product_status:known_affected": "53",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "HDF5: HDF5: Denial of Service via buffer underflow in H5Iget_name",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26199.json",
"version": "3"
},
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-26199\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-20T18:56:40.908924Z\"}}}], \"references\": [{\"url\": \"https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-20T18:56:18.160Z\"}}], \"cna\": {\"title\": \"Buffer underflow in `H5Iget_name `/`H5G_get_name` if size is zero\", \"source\": {\"advisory\": \"GHSA-5c6x-jmgf-f5vc\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 5.9, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"userInteraction\": \"ACTIVE\", \"attackComplexity\": \"HIGH\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\"}}], \"affected\": [{\"vendor\": \"HDFGroup\", \"product\": \"hdf5\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c= 1.14.6\"}]}], \"references\": [{\"url\": \"https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc\", \"name\": \"https://github.com/HDFGroup/hdf5/security/advisories/GHSA-5c6x-jmgf-f5vc\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/HDFGroup/hdf5/blob/develop/src/H5Gname.c#L474\", \"name\": \"https://github.com/HDFGroup/hdf5/blob/develop/src/H5Gname.c#L474\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"HDF5 is a high-performance library and a file format specification that implements the HDF5 data model. If `H5Iget_name` is invoked on a group id with `0` for the size parameter, it will underflow when trying to place a null terminator in the buffer. This can occur if `H5Iget_name` is invoked in a way where `size` can be forced to zero, and there is important data before the `name` buffer.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-124\", \"description\": \"CWE-124: Buffer Underwrite (\u0027Buffer Underflow\u0027)\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-07-20T14:59:35.038Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-26199\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-20T18:56:52.113Z\", \"dateReserved\": \"2026-02-11T19:56:24.813Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-07-20T14:59:35.038Z\", \"assignerShortName\": \"GitHub_M\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…