OpenBSD up to 7.8 ICMPv6 Neighbor Discovery Option nd_opt_len improper validation of specified quantity in input

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in OpenBSD up to 7.8. This impacts an unknown function of the component ICMPv6 Neighbor Discovery Option Handler. Such manipulation of the argument nd_opt_len leads to improper validation of specified quantity in input. This vulnerability is referenced as CVE-2026-41285. The attack needs to be initiated within the local network. No exploit is available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in OpenBSD up to 7.8. Affected by this issue is an unknown function of the component ICMPv6 Neighbor Discovery Option Handler. The manipulation of the argument nd_opt_len with an unknown input leads to a improper validation of specified quantity in input vulnerability. Using CWE to declare the problem leads to CWE-1284. The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties. Impacted is availability. CVE summarizes:

In OpenBSD through 7.8, the slaacd and rad daemons have an infinite loop when they receive a crafted ICMPv6 Neighbor Discovery (ND) option (over a local network) with length zero, because of an "nd_opt_len * 8 - 2" expression with no preceding check for whether nd_opt_len is zero.

The advisory is shared for download at rfc-editor.org. This vulnerability is handled as CVE-2026-41285 since 04/20/2026. The exploitation is known to be easy. The attack needs to approached within the local network. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

Applying the patch 086c5738bcd3c203bcc08d024fcf983cb409115f is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202604-4190) and CERT Bund (WID-SEC-2026-1184). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • OpenBSD OpenBSD

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.3
CNA Vector (MITRE): 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper validation of specified quantity in input
CWE: CWE-1284 / CWE-703
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

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: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 086c5738bcd3c203bcc08d024fcf983cb409115f

Timelineinfo

04/20/2026 CVE reserved
04/21/2026 +1 days Advisory disclosed
04/21/2026 +0 days VulDB entry created
04/22/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: rfc-editor.org
Status: Confirmed

CVE: CVE-2026-41285 (🔒)
GCVE (CVE): GCVE-0-2026-41285
GCVE (VulDB): GCVE-100-358400
CERT Bund: WID-SEC-2026-1184 - OpenBSD: Schwachstelle ermöglicht Denial of Service
CNNVD: CNNVD-202604-4190 - OpenBSD 安全漏洞

Entryinfo

Created: 04/21/2026 07:16
Updated: 04/22/2026 19:33
Changes: 04/21/2026 07:16 (65), 04/21/2026 11:17 (7), 04/22/2026 19:33 (6)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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