CVE-2026-49788: HTTP/2 Denial of Service Vulnerability

highCVSS 7.5CVE-2026-49788

Allocation of resources without limits or throttling in HTTP/2 allows an unauthorized attacker to deny service over a network.

CSIRTS triage

vendor: Microsoft product: HTTP/2 Denial of service

What: Allocation of resources without limits or throttling in HTTP/2 allows an unauthorized attacker to deny service over a network.
Who is affected: Deployments of systems using HTTP/2.
Urgency: Remediation is high urgency due to the potential for denial of service.
Action: Apply the latest updates for HTTP/2.

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

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.5
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49788

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-2026-497880.78% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 52% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-49788	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

Recent advisories for HTTP/2 Denial of

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.

high[UPDATE] [high] HTTP/2 implementations: Vulnerability allows denial of servicecert-bund · 2026-07-20
medium[NEW] [medium] HTTP/2 Server: Vulnerability allows Denial of Servicecert-bund · 2026-07-20
highCVE-2026-44453: h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 6b5370d, h…nvd · 2026-07-16
unknownCVE-2026-59246: Allocation of resources without limits vulnerability in elixir-mint mint allows a remote HTTP/…nvd · 2026-07-14
mediumCVE-2026-15713: Libsoup: soupcache: libsoup: http/2 frame window exhaustion remote denial of service via memor…msrc · 2026-07-14
high[UPDATE] [high] http/2 implementations: Vulnerability allows denial of servicecert-bund · 2026-07-06