IBM AIX/PowerVM VIOS IPv4 IP-options Parser integer underflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.7$5k-$25k0.00

Summaryinfo

A vulnerability marked as very critical has been reported in IBM AIX and PowerVM VIOS. This vulnerability affects unknown code of the component IPv4 IP-options Parser. The manipulation leads to integer underflow. This vulnerability is documented as CVE-2026-16839. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in IBM AIX and PowerVM VIOS (the affected version is unknown) and classified as very critical. This issue affects an unknown code of the component IPv4 IP-options Parser. The manipulation with an unknown input leads to a integer underflow vulnerability. Using CWE to declare the problem leads to CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a remote attacker to obtain sensitive information due to an integer underflow in the IPv4 IP-options parser.

The advisory is shared at ibm.com. The identification of this vulnerability is CVE-2026-16839 since 07/24/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/19/2026).

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

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.7
VulDB Meta Temp Score: 9.7

VulDB Base Score: 10.0
VulDB Temp Score: 10.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.4
CNA Vector (ibm): 🔒

CVSSv2info

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

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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

07/24/2026 CVE reserved
08/19/2026 +26 days Advisory disclosed
08/19/2026 +0 days VulDB entry created
08/19/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: ibm.com

Advisory: ibm.com
Status: Confirmed

CVE: CVE-2026-16839 (🔒)
GCVE (CVE): GCVE-0-2026-16839
GCVE (VulDB): GCVE-100-393341

Entryinfo

Created: 08/19/2026 21:58
Changes: 08/19/2026 21:58 (62)
Complete: 🔍
Cache ID: 216::103

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