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2 vulnerabilities by tatsuhiro-t
CVE-2026-40170 (GCVE-0-2026-40170)
Vulnerability from nvd – Published: 2026-04-16 21:34 – Updated: 2026-06-30 12:08
VLAI
Title
ngtcp2 has a qlog transport parameter serialization stack buffer overflow
Summary
ngtcp2 is a C implementation of the IETF QUIC protocol. In versions prior to 1.22.1, ngtcp2_qlog_parameters_set_transport_params() serializes peer transport parameters into a fixed 1024-byte stack buffer without bounds checking. When qlog is enabled, a remote peer can send sufficiently large transport parameters during the QUIC handshake to cause writes beyond the buffer boundary, resulting in a stack buffer overflow. This affects deployments that enable the qlog callback and process untrusted peer transport parameters. This issue has been fixed in version 1.22.1. If developers are unable to immediately upgrade, they can disable the qlog on client.
Severity
7.5 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
9 references
| URL | Tags |
|---|---|
| https://github.com/ngtcp2/ngtcp2/security/advisor… | x_refsource_CONFIRM |
| https://github.com/ngtcp2/ngtcp2/commit/708a7640c… | x_refsource_MISC |
| http://www.openwall.com/lists/oss-security/2026/0… | |
| https://access.redhat.com/security/cve/CVE-2026-40170 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2459061 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
| https://access.redhat.com/errata/RHSA-2026:22963 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:25049 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:9113 | vendor-advisoryx_refsource_REDHAT |
Impacted products
12 products
| Vendor | Product | Version | |
|---|---|---|---|
| ngtcp2 | ngtcp2 |
Affected:
< 1.22.1
|
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 10) |
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 9) |
cpe:/a:redhat:enterprise_linux:9::appstream |
|
| Red Hat | Red Hat Enterprise Linux BaseOS (v. 10) |
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux BaseOS (v. 9) |
cpe:/o:redhat:enterprise_linux:9::baseos |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) |
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) |
cpe:/a:redhat:enterprise_linux:9::crb |
|
| Red Hat | Red Hat Hardened Images |
cpe:/a:redhat:hummingbird:1 |
|
| Red Hat | Red Hat Enterprise Linux Resilient Storage (v. 9) |
cpe:/a:redhat:enterprise_linux:9::resilientstorage |
|
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10 |
|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8 |
|
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9 |
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CVE-2026-40170 (GCVE-0-2026-40170)
Vulnerability from cvelistv5 – Published: 2026-04-16 21:34 – Updated: 2026-06-30 12:08
VLAI
Title
ngtcp2 has a qlog transport parameter serialization stack buffer overflow
Summary
ngtcp2 is a C implementation of the IETF QUIC protocol. In versions prior to 1.22.1, ngtcp2_qlog_parameters_set_transport_params() serializes peer transport parameters into a fixed 1024-byte stack buffer without bounds checking. When qlog is enabled, a remote peer can send sufficiently large transport parameters during the QUIC handshake to cause writes beyond the buffer boundary, resulting in a stack buffer overflow. This affects deployments that enable the qlog callback and process untrusted peer transport parameters. This issue has been fixed in version 1.22.1. If developers are unable to immediately upgrade, they can disable the qlog on client.
Severity
7.5 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
9 references
| URL | Tags |
|---|---|
| https://github.com/ngtcp2/ngtcp2/security/advisor… | x_refsource_CONFIRM |
| https://github.com/ngtcp2/ngtcp2/commit/708a7640c… | x_refsource_MISC |
| http://www.openwall.com/lists/oss-security/2026/0… | |
| https://access.redhat.com/security/cve/CVE-2026-40170 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2459061 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
| https://access.redhat.com/errata/RHSA-2026:22963 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:25049 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:9113 | vendor-advisoryx_refsource_REDHAT |
Impacted products
12 products
| Vendor | Product | Version | |
|---|---|---|---|
| ngtcp2 | ngtcp2 |
Affected:
< 1.22.1
|
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 10) |
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux AppStream (v. 9) |
cpe:/a:redhat:enterprise_linux:9::appstream |
|
| Red Hat | Red Hat Enterprise Linux BaseOS (v. 10) |
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux BaseOS (v. 9) |
cpe:/o:redhat:enterprise_linux:9::baseos |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) |
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) |
cpe:/a:redhat:enterprise_linux:9::crb |
|
| Red Hat | Red Hat Hardened Images |
cpe:/a:redhat:hummingbird:1 |
|
| Red Hat | Red Hat Enterprise Linux Resilient Storage (v. 9) |
cpe:/a:redhat:enterprise_linux:9::resilientstorage |
|
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10 |
|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8 |
|
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9 |
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"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:25049"
},
{
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:9113"
}
],
"solutions": [
{
"lang": "en",
"value": "RHSA-2026:22963: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)"
},
{
"lang": "en",
"value": "RHSA-2026:25049: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Resilient Storage (v. 9)"
},
{
"lang": "en",
"value": "RHSA-2026:9113: Red Hat Hardened Images"
}
],
"timeline": [
{
"lang": "en",
"time": "2026-04-16T22:00:56.443Z",
"value": "Reported to Red Hat."
},
{
"lang": "en",
"time": "2026-04-16T21:34:07.610Z",
"value": "Made public."
}
],
"title": "ngtcp2: ngtcp2: Denial of service via stack buffer overflow during QUIC handshake",
"workarounds": [
{
"lang": "en",
"value": "To mitigate this issue, disable the `qlog` callback in applications utilizing the ngtcp2 library. This action prevents the vulnerable code path from being exercised when processing untrusted QUIC peer transport parameters. Disabling `qlog` may impact logging and debugging capabilities. Applications linked against ngtcp2 must be restarted for the change to take effect."
}
],
"x_adpType": "supplier",
"x_generator": {
"engine": "sadp-cli 1.0.0"
}
}
],
"cna": {
"affected": [
{
"product": "ngtcp2",
"vendor": "ngtcp2",
"versions": [
{
"status": "affected",
"version": "\u003c 1.22.1"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "ngtcp2 is a C implementation of the IETF QUIC protocol. In versions prior to 1.22.1, ngtcp2_qlog_parameters_set_transport_params() serializes peer transport parameters into a fixed 1024-byte stack buffer without bounds checking. When qlog is enabled, a remote peer can send sufficiently large transport parameters during the QUIC handshake to cause writes beyond the buffer boundary, resulting in a stack buffer overflow. This affects deployments that enable the qlog callback and process untrusted peer transport parameters. This issue has been fixed in version 1.22.1. If developers are unable to immediately upgrade, they can disable the qlog on client."
}
],
"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"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-121",
"description": "CWE-121: Stack-based Buffer Overflow",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-04-16T21:34:07.610Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/ngtcp2/ngtcp2/security/advisories/GHSA-f523-465f-8c8f",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/ngtcp2/ngtcp2/security/advisories/GHSA-f523-465f-8c8f"
},
{
"name": "https://github.com/ngtcp2/ngtcp2/commit/708a7640c1f48fb8ffb540c4b8ea5b4c1dfb8ee5",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/ngtcp2/ngtcp2/commit/708a7640c1f48fb8ffb540c4b8ea5b4c1dfb8ee5"
}
],
"source": {
"advisory": "GHSA-f523-465f-8c8f",
"discovery": "UNKNOWN"
},
"title": "ngtcp2 has a qlog transport parameter serialization stack buffer overflow"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-40170",
"datePublished": "2026-04-16T21:34:07.610Z",
"dateReserved": "2026-04-09T19:31:56.015Z",
"dateUpdated": "2026-06-30T12:08:58.286Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}