Suricata http1: quadratic complexity in headers parsing over multiple packets

published 2026-01-27 9 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-4771

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 38%
public exploits: 0; none known

Suricata is a network IDS, IPS and NSM engine. Starting in version 8.0.0 and prior to version 8.0.3, inefficiency in http1 headers parsing can lead to slowdown over multiple packets. Version 8.0.3 patches the issue. No known workarounds are available.

Patch / fix

fixed in 1 distros 2 links 1

oisf suricata 8.0.3

debian opensuse

suricata Debian 14 1:8.0.3-1

debian advisories DEBIAN-CVE-2026-22263

suricata openSUSE Tumbleweed 8.0.3-1.1

opensuse advisories openSUSE-SU-2026:10082-1

github.com/OISF/suricata@018a377 commit

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-22263 updated 2026-06-28 cvss 5.3

suricata: Suricata: Denial of Service via inefficient HTTP/1 header parsing

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 9 mo ago (2026-01-27)

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

OISF suricata

Classification

Weakness

CWE-1050 Excessive Platform Resource Consumption within a Loop

References

github.com /OISF/suricata/commit/018a377f74e3eb2b042c6f783ad9043060923428
patch
github.com /OISF/suricata/security/advisories/GHSA-rwc5-hxj6-hwx7
vendor-advisory
redmine.openinfosecfoundation.org /issues/8201
permissions-required

Sources

CVE List CVE-2026-22263
NVD CVE-2026-22263

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.

Summary