CVE-2026-13763: AWS Application Load Balancer · HTTP Request/Response smuggling
Affects AWS Application Load BalancerSource CVE Database V5
Not known to be exploited · CVSS 9.8 Critical · patch available : patch AWS Application Load Balancer as a priority.
Data as of 12 Nov 2026, 23:24 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 52% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 29 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| AWSAWS Application Load Balancer | Affected
| Fixed in– |
AI-suggested
AWS manages remediation for this cloud-hosted service. Customers should enable the "Inspect after sufficient data" target group configuration on their HTTP/2 ALB target groups as documented by AWS (https://docs.aws.amazon.com/elasticloadbalancing/latest/application/edit-target-group-attributes.html#waf-http2-inspection). This setting ensures that AWS WAF inspects the full request body, preventing bypass via fragmented HTTP/2 requests. Refer to the official AWS security bulletin for updates and guidance: https://aws.amazon.com/security/security-bulletins/2026-048-aws/
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 )