CVE-2023-25725

CVE Enrichment

CVSS: 9.1 CRITICAL
EPSS: 5.45%
EPSS Percentile: 92.66%
CISA KEV: Not listed

Description

HAProxy before 2.7.3 may allow a bypass of access control because HTTP/1 headers are inadvertently lost in some situations, aka "request smuggling." The HTTP header parsers in HAProxy may accept empty header field names, which could be used to truncate the list of HTTP headers and thus make some headers disappear after being parsed and processed for HTTP/1.0 and HTTP/1.1. For HTTP/2 and HTTP/3, the impact is limited because the headers disappear before being parsed and processed, as if they had not been sent by the client. The fixed versions are 2.7.3, 2.6.9, 2.5.12, 2.4.22, 2.2.29, and 2.0.31.

Technical Details

CVSS Version: 3.1
CNA / NVD Source: cve@mitre.org
Published: 15-Feb-2023 02:15
Last Modified: 17-Jun-2026 12:41
EPSS Date: 2026-10-20
CWE: CWE-444

CVSS Vector


            CVSS:3.1                            AV:N /
                            AC:L /
                            PR:N /
                            UI:N /
                            S:U /
                            C:N /
                            I:H /
                            A:H

Affected Products / Versions

haproxy / haproxy
Version / affected range: * · before (exclusive) 2.0.31
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*
haproxy / haproxy
Version / affected range: * · from (inclusive) 2.1.0 · before (exclusive) 2.2.29
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*
haproxy / haproxy
Version / affected range: * · from (inclusive) 2.3.0 · before (exclusive) 2.4.22
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*
haproxy / haproxy
Version / affected range: * · from (inclusive) 2.5.0 · before (exclusive) 2.5.12
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*
haproxy / haproxy
Version / affected range: * · from (inclusive) 2.6.0 · before (exclusive) 2.6.9
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*
haproxy / haproxy
Version / affected range: * · from (inclusive) 2.7.0 · before (exclusive) 2.7.3
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*
debian / debian_linux
Version / affected range: 10.0
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian / debian_linux
Version / affected range: 11.0
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References

Last enrichment sync: 21-Oct-2026 17:07
Sources: NVD · FIRST EPSS · CISA KEV
Latest successful provider update; providers refresh independently.

Reported Context (1)

The SHELLCODE NOP Sled signature dropped from #3 to #24, and the HAProxy header bypass (`CVE-2023-25725`) fell from #2 to #36 by volume. WatchGuard H1 2026 Report Finds More Novel Malware Despite Falling Network Detections

CVE (7)

Malware (10)

Threat Actors (4)

MITRE ATT&CK (15)

Vendors (2)

Products (10)

Tools (3)

Countries (10)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.