IBM i 7.3/7.4/7.5/7.6 NetServer integer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.5$5k-$25k1.51

Summaryinfo

A vulnerability has been found in IBM i 7.3/7.4/7.5/7.6 and classified as critical. This affects an unknown part of the component NetServer. This manipulation causes integer overflow. This vulnerability is registered as CVE-2026-18671. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability has been found in IBM i 7.3/7.4/7.5/7.6 and classified as critical. Affected by this vulnerability is an unknown part of the component NetServer. The manipulation with an unknown input leads to a integer overflow vulnerability. The CWE definition for the vulnerability is CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. As an impact it is known to affect availability. The summary by CVE is:

IBM i 7.6, 7.5, 7.4, and 7.3 could allow an authenticated attacker to force a NetServer server thread exception, caused by an integer overflow during bounds checking in request processing. The attacker could exploit this vulnerability to cause a temporary denial of service.

It is possible to read the advisory at ibm.com. This vulnerability is known as CVE-2026-18671 since 08/03/2026. The exploitation appears to be easy. The attack can be launched remotely. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/14/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-58473). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.5

VulDB Base Score: 6.5
VulDB Temp Score: 6.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/03/2026 CVE reserved
08/13/2026 +10 days Advisory disclosed
08/13/2026 +0 days VulDB entry created
08/14/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: ibm.com

Advisory: ibm.com
Status: Confirmed

CVE: CVE-2026-18671 (🔒)
GCVE (CVE): GCVE-0-2026-18671
GCVE (VulDB): GCVE-100-389875
EUVD: 🔒

Entryinfo

Created: 08/13/2026 23:05
Updated: 08/14/2026 00:07
Changes: 08/13/2026 23:05 (53), 08/14/2026 00:07 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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