Apache APISIX: Forward-Auth Request Smuggling

published 2024-05-02 2 y ago modified 2026-09-08 2 mo ago also BIT-apisix-2024-32638 , EUVD-2024-30440

cvss: 6.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 64%
public exploits: 0; none known

Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in Apache APISIX when using `forward-auth` plugin.This issue affects Apache APISIX: from 3.8.0, 3.9.0.

Users are recommended to upgrade to version 3.8.1, 3.9.1 or higher, which fixes the issue.

Patch / fix

fixed in 2

bitnami apisix 3.9.1
apache apisix 3.8.1, 3.9.1

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-05-02)

Exploit prediction

1.06% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
CNA	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
OSV	3.1	6.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Affected packages

ecosystem	package	affected	fixed in
bitnami	apisix	>=3.8.0, <3.9.1	3.9.1

Affected products

Apache Software Foundation Apache APISIX
apache_software_foundation Apache_APISIX

Classification

Weakness

CWE-444 Inconsistent Interpretation of HTTP Requests

References

lists.apache.org /thread/ngvgxllw4zn4hgngkqw2o225kf9wotov
vendor-advisory, mailing-list, advisory
openwall.com /lists/oss-security/2024/05/02/2
mailing-list, third-party-advisory, advisory
nvd.nist.gov /vuln/detail/CVE-2024-32638
web

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary