CVE-2026-18077

IBM i is Affected By Multiple Vulnerabilities in Simple Mail Transfer Protocol

Published Aug 13, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Description

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to cause a denial of service due to a stack-based buffer overflow.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

IBM

affected

Version	Status	Constraints
`7.6`	affected	—
`7.5`	affected	—
`7.4`	affected	—
`7.3`	affected	—

Configuration 1 [-]

OR	cpe:2.3:o:ibm:i:7.3:::::::*
	cpe:2.3:o:ibm:i:7.4:::::::*
	cpe:2.3:o:ibm:i:7.5:::::::*
	cpe:2.3:o:ibm:i:7.6:::::::*

No data.

Vendor Product Versions

Ibm

Version	Status	Scheme	Platform
`7.6`	affected	generic	—
`7.5`	affected	generic	—
`7.4`	affected	generic	—
`7.3`	affected	generic	—

Remediation

Vendor Solution

IBM strongly recommends addressing the vulnerability now. IBM i Release5770-TC1 PTF Number(s)PTF Download Link(s)7.6SJ11061 SJ11131 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11061 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11131 7.5SJ11074 SJ11129 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11074 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11129 7.4SJ11083 SJ11127 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11083 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11127 7.3SJ11084 SJ11123 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11084 https://www.ibm.com/mysupport/s/fix-information?legacy=SJ11123 https://www.ibm.com/mysupport/s/fix-information IBM recommends users running unsupported versions of affected products upgrade to a supported and fixed version of affected products.

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.546% probability within 30 days)

Exploitation none

Automatable yes

Technical Impact partial

References

Link	Providers
https://www.ibm.com/support/pages/node/7283291

History

Aug 19, 2026 4:45 PM Affected versions updated View changes

Type	Values Removed	Values Added
CPEs		cpe:2.3:o:ibm:i:7.3:::::::* cpe:2.3:o:ibm:i:7.4:::::::* cpe:2.3:o:ibm:i:7.5:::::::* cpe:2.3:o:ibm:i:7.6:::::::*

Aug 18, 2026 2:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Aug 13, 2026 9:00 PM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to cause a denial of service due to a stack-based buffer overflow.
Title		IBM i is Affected By Multiple Vulnerabilities in Simple Mail Transfer Protocol
First Time appeared		Ibm Ibm i
Weaknesses		CWE-787
CPEs		cpe:2.3:a:ibm:i:7.3.0:::::::* cpe:2.3:a:ibm:i:7.3:::::::* cpe:2.3:a:ibm:i:7.4.0:::::::* cpe:2.3:a:ibm:i:7.4:::::::* cpe:2.3:a:ibm:i:7.5.0:::::::* cpe:2.3:a:ibm:i:7.5:::::::* cpe:2.3:a:ibm:i:7.6.0:::::::* cpe:2.3:a:ibm:i:7.6:::::::*
Vendors & Products		Ibm Ibm i
References		https://www.ibm.com/support/pages/node/7283291
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}`