7.5

CVE-2026-40170

Exploit

ngtcp2 has a qlog transport parameter serialization stack buffer overflow

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Tatsuhiro-t ≫ Ngtcp2 Version < 1.22.1
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.78% 0.512
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
0b0ca135-0b70-47e7-9f44-1890c2a1c46c 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

CWE-121 Stack-based Buffer Overflow

A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

https://github.com/ngtcp2/ngtcp2/commit/708a7640c1f48fb8ffb540c4b8ea5b4c1dfb8ee5
Patch
http://www.openwall.com/lists/oss-security/2026/04/17/12
Patch
Third Party Advisory
Exploit
Mailing List
Mitigation
https://bugzilla.redhat.com/show_bug.cgi?id=2459061
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40170.json
https://github.com/ngtcp2/ngtcp2/security/advisories/GHSA-f523-465f-8c8f
Patch
Vendor Advisory
Exploit
Mitigation
https://access.redhat.com/errata/RHSA-2026:22963
https://access.redhat.com/errata/RHSA-2026:25049
https://access.redhat.com/errata/RHSA-2026:9113
https://access.redhat.com/security/cve/CVE-2026-40170