CVE-2026-14456: Unbounded Memory Growth in QUIC Server Incoming Channel Queue

highCVSS 7.5CVE-2026-14456

CSIRTS triage

Denial of service Memory corruption

What: Unbounded memory growth in a QUIC server's incoming channel queue leading to denial of service.
Who is affected: QUIC server implementations with this vulnerability in the incoming channel queue handling are affected.
Urgency: High severity with CVSS 7.5 due to resource exhaustion potential; no active exploitation reported.
Action: Identify and update the affected QUIC implementation to a patched version.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-14456

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-144560.61% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 47% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-14456	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownUSN-8678-1: OpenSSL vulnerabilitiesubuntu
unknownDSA-6465-1 openssl - security updatedebian
medium[NEW] [medium] OpenSSL: Vulnerability enables denial of servicecert-bund
unknownVulnerability in OpenSSL (August 14, 2026)cert-fr-avis
highCVE-2026-14456: Issue summary: When an OpenSSL QUIC server (Listener SSL object) processes valid QUIC Initial …nvd

Recent advisories for Unbounded Memory Growth

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-34183: Unbounded Memory Growth in the QUIC PATH_CHALLENGE Handlermsrc · 2026-08-06
mediumGHSA-6hxr-mr5r-9836: re2: Global `String.prototype.match` with an empty-matchable pattern never advances → inf…ghsa · 2026-07-31
highGHSA-xpxj-f2fm-rqch: OliveTin: Unauthenticated DoS via OAuth2 State Memory Exhaustion (Unbounded Map Growth)ghsa · 2026-07-30
mediumCVE-2026-59848: A flaw was found in libssh. A malicious SFTP server can send responses for unknown request IDs…nvd · 2026-07-21
mediumCVE-2026-8609: An unauthenticated attacker can repeatedly call Grafana's OAuth login route with unique values,…nvd · 2026-07-10
mediumGHSA-c2f9-4mc8-j656: pyLoad: Unbounded Memory Growth Leading to DoS and Potential DDoS in EventManagerghsa · 2026-07-09