CVE-2026-7423 (GCVE-0-2026-7423)
Vulnerability from cvelistv5 – Published: 2026-04-29 18:36 – Updated: 2026-04-29 19:08
VLAI?
Title
Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP
Summary
Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB.
To mitigate this issue, users should upgrade to the fixed version when available.
Severity ?
CWE
- CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
References
| URL | Tags | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| AWS | FreeRTOS-Plus-TCP |
Affected:
4.0.0 , < 4.2.6
(semver)
Affected: 4.3.0 , < 4.4.1 (semver) Unaffected: 4.2.6 Unaffected: 4.4.1 |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-7423",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-04-29T19:08:03.742434Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-04-29T19:08:11.602Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://github.com/FreeRTOS/FreeRTOS-Plus-TCP",
"defaultStatus": "unaffected",
"product": "FreeRTOS-Plus-TCP",
"vendor": "AWS",
"versions": [
{
"lessThan": "4.2.6",
"status": "affected",
"version": "4.0.0",
"versionType": "semver"
},
{
"lessThan": "4.4.1",
"status": "affected",
"version": "4.3.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "4.2.6"
},
{
"status": "unaffected",
"version": "4.4.1"
}
]
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "\u003cp\u003eInteger underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB.\u003c/p\u003e\u003cp\u003eTo mitigate this issue, users should upgrade to the fixed version when available.\u003c/p\u003e"
}
],
"value": "Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB.\n\n\n\nTo mitigate this issue, users should upgrade to the fixed version when available."
}
],
"impacts": [
{
"capecId": "CAPEC-153",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-153: Input Data Manipulation"
}
]
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "ADJACENT_NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 5.3,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
},
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "ADJACENT",
"baseScore": 6,
"baseSeverity": "MEDIUM",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-191",
"description": "CWE-191: Integer Underflow (Wrap or Wraparound)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-04-29T18:50:12.168Z",
"orgId": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"shortName": "AMZN"
},
"references": [
{
"tags": [
"patch"
],
"url": "https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1"
},
{
"tags": [
"patch"
],
"url": "https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6"
},
{
"tags": [
"vendor-advisory"
],
"url": "https://aws.amazon.com/security/security-bulletins/2026-021-aws/"
},
{
"tags": [
"third-party-advisory"
],
"url": "https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-7r59-2pgv-9v2r"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP",
"x_generator": {
"engine": "Vulnogram 1.0.1"
}
}
},
"cveMetadata": {
"assignerOrgId": "ff89ba41-3aa1-4d27-914a-91399e9639e5",
"assignerShortName": "AMZN",
"cveId": "CVE-2026-7423",
"datePublished": "2026-04-29T18:36:28.353Z",
"dateReserved": "2026-04-29T14:27:49.474Z",
"dateUpdated": "2026-04-29T19:08:11.602Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-7423",
"date": "2026-05-04",
"epss": "0.00015",
"percentile": "0.03401"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-7423\",\"sourceIdentifier\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"published\":\"2026-04-29T19:16:26.617\",\"lastModified\":\"2026-05-04T13:35:00.500\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB.\\n\\n\\n\\nTo mitigate this issue, users should upgrade to the fixed version when available.\"}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/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\":6.0,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"ADJACENT\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"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\"}}],\"cvssMetricV31\":[{\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":5.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"ADJACENT_NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.6,\"impactScore\":3.6},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"ADJACENT_NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":3.6}]},\"weaknesses\":[{\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-191\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:amazon:freertos-plus-tcp:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.0.0\",\"versionEndExcluding\":\"4.2.6\",\"matchCriteriaId\":\"DE7A5C38-9CEA-461B-9272-3B8BFC06BFEE\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:amazon:freertos-plus-tcp:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.3.0\",\"versionEndExcluding\":\"4.4.1\",\"matchCriteriaId\":\"375C7032-9CFB-480C-BFFA-029C985A82B7\"}]}]}],\"references\":[{\"url\":\"https://aws.amazon.com/security/security-bulletins/2026-021-aws/\",\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6\",\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"tags\":[\"Release Notes\"]},{\"url\":\"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1\",\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"tags\":[\"Release Notes\"]},{\"url\":\"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-7r59-2pgv-9v2r\",\"source\":\"ff89ba41-3aa1-4d27-914a-91399e9639e5\",\"tags\":[\"Vendor Advisory\",\"Patch\"]}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-7423\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-04-29T19:08:03.742434Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-04-29T19:08:07.142Z\"}}], \"cna\": {\"title\": \"Integer Underflow in ICMP Echo Reply Processing in FreeRTOS-Plus-TCP\", \"source\": {\"discovery\": \"UNKNOWN\"}, \"impacts\": [{\"capecId\": \"CAPEC-153\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-153: Input Data Manipulation\"}]}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.3, \"attackVector\": \"ADJACENT_NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}, {\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 6, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"ADJACENT\", \"baseSeverity\": \"MEDIUM\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"AWS\", \"product\": \"FreeRTOS-Plus-TCP\", \"versions\": [{\"status\": \"affected\", \"version\": \"4.0.0\", \"lessThan\": \"4.2.6\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"4.3.0\", \"lessThan\": \"4.4.1\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"4.2.6\"}, {\"status\": \"unaffected\", \"version\": \"4.4.1\"}], \"collectionURL\": \"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP\", \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6\", \"tags\": [\"patch\"]}, {\"url\": \"https://aws.amazon.com/security/security-bulletins/2026-021-aws/\", \"tags\": [\"vendor-advisory\"]}, {\"url\": \"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-7r59-2pgv-9v2r\", \"tags\": [\"third-party-advisory\"]}], \"x_generator\": {\"engine\": \"Vulnogram 1.0.1\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Integer underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB.\\n\\n\\n\\nTo mitigate this issue, users should upgrade to the fixed version when available.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eInteger underflow in the ICMP and ICMPv6 echo reply handlers in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network user to cause a denial of service (device crash) when outgoing ping support is enabled, because header sizes are subtracted from a packet length field without validating the field is large enough, resulting in a heap out-of-bounds read of up to approximately 65KB.\u003c/p\u003e\u003cp\u003eTo mitigate this issue, users should upgrade to the fixed version when available.\u003c/p\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-191\", \"description\": \"CWE-191: Integer Underflow (Wrap or Wraparound)\"}]}], \"providerMetadata\": {\"orgId\": \"ff89ba41-3aa1-4d27-914a-91399e9639e5\", \"shortName\": \"AMZN\", \"dateUpdated\": \"2026-04-29T18:50:12.168Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-7423\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-04-29T19:08:11.602Z\", \"dateReserved\": \"2026-04-29T14:27:49.474Z\", \"assignerOrgId\": \"ff89ba41-3aa1-4d27-914a-91399e9639e5\", \"datePublished\": \"2026-04-29T18:36:28.353Z\", \"assignerShortName\": \"AMZN\"}",
"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…