CVE-2026-55995

Publication date 29 July 2026

Last updated 22 September 2026

Ubuntu priority

Description

A Double Free vulnerability in open-iscsi allows an unauthenticated MITM attacker to cause DoS. This issue affects open-iscsi: from ? through 56718d4e9d1a4f51c30697b5c0534144bb41c9bb.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
open-iscsi	26.04 LTS resolute	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Needs evaluation
open-isns	26.04 LTS resolute	Vulnerable
	24.04 LTS noble	Vulnerable
	22.04 LTS jammy	Vulnerable
	20.04 LTS focal	Vulnerable
	18.04 LTS bionic	Vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
open-isns	Upstream: 56718d4

Severity score breakdown

CVSS version: CVSS v4.0

Base score 8.7 · High

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	None
Vulnerable system - Confidentiality impact	None
Vulnerable system - Integrity impact	None
Vulnerable system - Availability impact	High
Subsequent system - Confidentiality impact	None
Subsequent system - Integrity impact	None
Subsequent system - Availability impact	None

Scores

Parameter	Value
Base score	8.7 · High
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References

Related Ubuntu Security Notices (USN)

USN-8807-1
Open-iSNS vulnerability
23 September 2026

Other references

https://www.cve.org/CVERecord?id=CVE-2026-55995