CVE-2025-53538

Suricata's mishandling of data on HTTP2 stream 0 can lead to resource starvation

7.5 HighFix available

Suricata is a network IDS, IPS and NSM engine developed by the OISF (Open Information Security Foundation) and the Suricata community. In versions 7.0.10 and below and 8.0.0-beta1 through 8.0.0-rc1, mishandling of data on HTTP2 stream 0 can lead to uncontrolled memory usage, leading to loss of visibility. Workarounds include disabling the HTTP/2 parser, and using a signature like drop http2 any any -> any any (frame:http2.hdr; byte_test:1,=,0,3; byte_test:4,=,0,5; sid: 1;) where the first byte test tests the HTTP2 frame type DATA and the second tests the stream id 0. This is fixed in versions 7.0.11 and 8.0.0.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

0.54%Up 0.5 points since Jul 23, 2025

What each source reports

CVE List Score used 7.5

Suricata's mishandling of data on HTTP2 stream 0 can lead to resource starvation

Record: CVE-2025-53538
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-770, CWE-400
Updated: 2026-11-02

EUVDEUVD-2025-22378 7.5

Record: EUVD-2025-22378
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

NVD 7.5

Record: CVE-2025-53538
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

OSV 7.5

Suricata's mishandling of data on HTTP2 stream 0 can lead to resource starvation

Record: CVE-2025-53538
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

OSVDEBIAN-CVE-2025-53538 7.5

Record: DEBIAN-CVE-2025-53538
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVUBUNTU-CVE-2025-53538 7.5

Record: UBUNTU-CVE-2025-53538
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

Affected products

oisf suricata

Affected packages

Affected packages
Package	Affected	Fixed
`suricata` Debian:13	before 1:7.0.10-1+deb13u1, plus listed versions 1:7.0.10-1	1:7.0.10-1+deb13u1
`suricata` Debian:14	before 1:7.0.11-1, plus listed versions 1:7.0.10-11:7.0.11-1~bpo13+1	1:7.0.11-1
`suricata` Ubuntu:16.04:LTS	All versions, plus listed versions 2.0.8-1build12.0.9-12.0.10-12.0.10-22.0.11-13.0-1	None known
`suricata` Ubuntu:18.04:LTS	All versions, plus listed versions 3.2-2ubuntu3	None known
`suricata` Ubuntu:22.04:LTS	All versions, plus listed versions 1:6.0.4-21:6.0.4-3	None known
`suricata` Ubuntu:24.04:LTS	All versions, plus listed versions 1:7.0.0-21:7.0.2-11:7.0.2-1build11:7.0.3-1build11:7.0.3-1build3	None known
`suricata` Ubuntu:25.10	All versions, plus listed versions 1:7.0.8-21:7.0.10-1	None known
`suricata` Ubuntu:26.10	All versions, plus listed versions 1:8.0.3-11:8.0.5-11:8.0.6-1	None known
`suricata` Ubuntu:26.04:LTS	All versions, plus listed versions 1:7.0.10-11:8.0.1-3build11:8.0.2-11:8.0.2-1build11:8.0.3-1	None known

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2025-53538 is a high vulnerability (CVSS 7.5) in Oisf Suricata, published July 22, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.54%, the 45th percentile. Fixed in suricata 1:7.0.10-1+deb13u1.