CVE-2026-73276: inets, httpd: HTTP Request Smuggling via Whitespace-Before-Colon Header Dropping i

Severity: high (CVSS 8.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-01 · updated 2026-09-08
Weakness: CWE-444

Description

Gracefulness code ignored cases that should be rejected, resulting in possible HTTP Request Smuggling opportunities. This issue affects OTP from OTP 22.2 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets from 7.1.2 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2.

Affected products

Erlang OTP: from 22.2 before 27.3.4.17; from 28.0 before 28.5.0.6; from 29.0 before 29.0.6; from 7.1.2 before 9.3.2.7; from 9.4 before 9.6.2.3; from 9.7 before 9.7.2 — fixed in 27.3.4.17, 28.5.0.6, 29.0.6, 9.3.2.7, 9.6.2.3, 9.7.2

How to fix

Upgrade to a fixed version: Erlang OTP 27.3.4.17, 28.5.0.6, 29.0.6, 9.3.2.7. Check the vendor advisory for mitigations.

References

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