CVE-2026-13763 HTTP/2 Stream Parser Confusion Body-Inspection Bypass in AWS Application Load Balancer with AWS WAF
Remote attackers can bypass AWS WAF body inspection on HTTP/2 ALB target groups by fragmenting request bodies, requiring configuration changes to mitigate.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-13763?
CVE-2026-13763 is a high-severity vulnerability in AWS Application Load Balancer, published on 29 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Inconsistent interpretation of HTTP/2 requests in AWS Application Load Balancer with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the request body across frames so that only a partial body is inspected. This issue only impacts HTTP/2 ALB target groups.
To remediate this issue, customers should enable the "Inspect after sufficient data" target group configuration associated to an ALB load balancer. Refer to: ( https://docs.aws.amazon.com/elasticloadbalancing/latest/application/edit-target-group-attributes.html#waf-http2-inspection )
Weakness: CWE-444
Which versions are affected by CVE-2026-13763?
It affects 1 product.
Products include Amazon Application Load Balancer.
How do I fix CVE-2026-13763?
No fix has been published for CVE-2026-13763 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-13763 being exploited?
There is no known exploitation of CVE-2026-13763 in the wild and no public exploit code.
Sources
Also known as GHSA-9m3p-hghr-5v6c.