CVE-2026-110353 (GCVE-0-2026-110353)
Vulnerability from cvelistv5 – Published: 2026-10-22 02:53 – Updated: 2026-10-22 02:53
VLAI
EPSS
VEX
Summary
HAProxy 3.2 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (worker-thread CPU exhaustion) via a truncated HTTP/2 PING frame. h2c_handle_ping in src/mux_h2.c does not check for a short read, unlike the other H2 frame handlers. Because the incomplete frame cannot be processed, its data is never consumed, and the H2 multiplexer tasklet is repeatedly woken by that pending data without making progress. The CPU spins until timeout http-request closes the connection, and an attacker opening many such connections can sustain high CPU usage.
Severity
7.5 (High)
CWE
- CWE-252 - Unchecked Return Value
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://git.haproxy.org/?p=haproxy.git;a=commit;h… | vendor-advisory |
Impacted products
4 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| HAProxy | HAProxy |
Affected:
3.2.0 , < 3.2.26
(custom)
Affected: 3.3.0 , < 3.3.17 (custom) Affected: 3.4.0 , < 3.4.6 (custom) Affected: 3.5-dev , < 3.5-dev9 (custom) |
guessed | |
| HAProxy | HAProxy Enterprise Edition |
Affected:
3.2.0r1 , < 3.2r1-378.1259
(custom)
Affected: 3.3.0r1 , < 3.3r1-377.1005 (custom) |
guessed | |
| HAProxy | Kubernetes Ingress Controller |
Affected:
3.2.0 , < 3.2.17
(custom)
|
guessed | |
| Haproxy | Kubernetes Ingress Controller Enterprise |
Affected:
3.2.0 , < 3.2.17-ee1
(custom)
Affected: 3.0 , < 3.0.16-ee17 (custom) Affected: 1.11 , < 1.11.14-ee11 (custom) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"modules": [
"mux-h2"
],
"product": "HAProxy",
"programFiles": [
"src/mux_h2.c"
],
"programRoutines": [
{
"name": "h2c_handle_ping"
}
],
"repo": "https://git.haproxy.org/git/haproxy.git/",
"vendor": "HAProxy",
"versions": [
{
"lessThan": "3.2.26",
"status": "affected",
"version": "3.2.0",
"versionType": "custom"
},
{
"lessThan": "3.3.17",
"status": "affected",
"version": "3.3.0",
"versionType": "custom"
},
{
"lessThan": "3.4.6",
"status": "affected",
"version": "3.4.0",
"versionType": "custom"
},
{
"lessThan": "3.5-dev9",
"status": "affected",
"version": "3.5-dev",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unaffected",
"product": "HAProxy Enterprise Edition",
"vendor": "HAProxy",
"versions": [
{
"lessThan": "3.2r1-378.1259",
"status": "affected",
"version": "3.2.0r1",
"versionType": "custom"
},
{
"lessThan": "3.3r1-377.1005",
"status": "affected",
"version": "3.3.0r1",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unaffected",
"product": "Kubernetes Ingress Controller",
"vendor": "HAProxy",
"versions": [
{
"lessThan": "3.2.17",
"status": "affected",
"version": "3.2.0",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unaffected",
"product": "Kubernetes Ingress Controller Enterprise",
"vendor": "Haproxy",
"versions": [
{
"lessThan": "3.2.17-ee1",
"status": "affected",
"version": "3.2.0",
"versionType": "custom"
},
{
"lessThan": "3.0.16-ee17",
"status": "affected",
"version": "3.0",
"versionType": "custom"
},
{
"lessThan": "1.11.14-ee11",
"status": "affected",
"version": "1.11",
"versionType": "custom"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "HAProxy 3.2 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (worker-thread CPU exhaustion) via a truncated HTTP/2 PING frame. h2c_handle_ping in src/mux_h2.c does not check for a short read, unlike the other H2 frame handlers. Because the incomplete frame cannot be processed, its data is never consumed, and the H2 multiplexer tasklet is repeatedly woken by that pending data without making progress. The CPU spins until timeout http-request closes the connection, and an attacker opening many such connections can sustain high CPU usage."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-252",
"description": "CWE-252 Unchecked Return Value",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-10-22T02:53:33.198Z",
"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"shortName": "mitre"
},
"references": [
{
"tags": [
"vendor-advisory"
],
"url": "https://git.haproxy.org/?p=haproxy.git;a=commit;h=cec63e95f62a7412484f1134f5aa227e5b7e1466"
}
],
"x_generator": {
"engine": "CVE-Request-form 0.0.1"
}
}
},
"cveMetadata": {
"assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"assignerShortName": "mitre",
"cveId": "CVE-2026-110353",
"datePublished": "2026-10-22T02:53:33.198Z",
"dateReserved": "2026-10-13T23:18:04.062Z",
"dateUpdated": "2026-10-22T02:53:33.198Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-110353",
"date": "2026-10-22",
"epss": "0.00684",
"percentile": "0.51989"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"modules": [
"mux-h2"
],
"product": "HAProxy",
"programFiles": [
"src/mux_h2.c"
],
"programRoutines": [
{
"name": "h2c_handle_ping"
}
],
"repo": "https://git.haproxy.org/git/haproxy.git/",
"vendor": "HAProxy",
"versions": [
{
"lessThan": "3.2.26",
"status": "affected",
"version": "3.2.0",
"versionType": "custom"
},
{
"lessThan": "3.3.17",
"status": "affected",
"version": "3.3.0",
"versionType": "custom"
},
{
"lessThan": "3.4.6",
"status": "affected",
"version": "3.4.0",
"versionType": "custom"
},
{
"lessThan": "3.5-dev9",
"status": "affected",
"version": "3.5-dev",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unaffected",
"product": "HAProxy Enterprise Edition",
"vendor": "HAProxy",
"versions": [
{
"lessThan": "3.2r1-378.1259",
"status": "affected",
"version": "3.2.0r1",
"versionType": "custom"
},
{
"lessThan": "3.3r1-377.1005",
"status": "affected",
"version": "3.3.0r1",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unaffected",
"product": "Kubernetes Ingress Controller",
"vendor": "HAProxy",
"versions": [
{
"lessThan": "3.2.17",
"status": "affected",
"version": "3.2.0",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unaffected",
"product": "Kubernetes Ingress Controller Enterprise",
"vendor": "Haproxy",
"versions": [
{
"lessThan": "3.2.17-ee1",
"status": "affected",
"version": "3.2.0",
"versionType": "custom"
},
{
"lessThan": "3.0.16-ee17",
"status": "affected",
"version": "3.0",
"versionType": "custom"
},
{
"lessThan": "1.11.14-ee11",
"status": "affected",
"version": "1.11",
"versionType": "custom"
}
]
}
],
"source": "cve@mitre.org"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "HAProxy 3.2 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (worker-thread CPU exhaustion) via a truncated HTTP/2 PING frame. h2c_handle_ping in src/mux_h2.c does not check for a short read, unlike the other H2 frame handlers. Because the incomplete frame cannot be processed, its data is never consumed, and the H2 multiplexer tasklet is repeatedly woken by that pending data without making progress. The CPU spins until timeout http-request closes the connection, and an attacker opening many such connections can sustain high CPU usage."
}
],
"id": "CVE-2026-110353",
"lastModified": "2026-10-22T03:16:31.270",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 3.6,
"source": "cve@mitre.org",
"type": "Secondary"
}
]
},
"published": "2026-10-22T03:16:31.270",
"references": [
{
"source": "cve@mitre.org",
"url": "https://git.haproxy.org/?p=haproxy.git;a=commit;h=cec63e95f62a7412484f1134f5aa227e5b7e1466"
}
],
"sourceIdentifier": "cve@mitre.org",
"vulnStatus": "Received",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-252"
}
],
"source": "cve@mitre.org",
"type": "Primary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Important",
"current_release_date": "2026-10-22T10:17:57+00:00",
"cve": "CVE-2026-110353",
"id": "CVE-2026-110353",
"initial_release_date": "2026-10-22T02:53:33.198000+00:00",
"product_status:known_affected": "16",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "haproxy: HAProxy: Denial of Service via truncated HTTP/2 PING frame",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-110353.json",
"version": "3"
}
}
}
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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