osrg GoBGP up to 4.6.x BGP UPDATE Validator denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.6$0-$5k0.00+

Summaryinfo

A vulnerability described as critical has been identified in osrg GoBGP up to 4.6.x. This issue affects some unknown processing of the component BGP UPDATE Validator. Executing a manipulation can lead to denial of service. The identification of this vulnerability is CVE-2026-49838. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in osrg GoBGP up to 4.6.x. This vulnerability affects an unknown code block of the component BGP UPDATE Validator. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. CVE summarizes:

GoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language. Prior to version 4.7.0, GoBGP accepts a zero-length AS_PATH during UPDATE decoding and later panics while validating that attribute for a confederation eBGP peer. The vulnerable path is in the BGP UPDATE validator: a malformed UPDATE that should be rejected as a malformed AS_PATH instead reaches an unchecked `p.Value[0]` access, allowing a configured confederation eBGP peer to trigger a denial of service. Version 4.7.0 patches the issue.

The advisory is available at github.com. This vulnerability was named CVE-2026-49838 since 06/01/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 4.7.0 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.9
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: GoBGP 4.7.0

Timelineinfo

06/01/2026 CVE reserved
09/10/2026 +101 days VulDB entry created
09/11/2026 +0 days Advisory disclosed
09/11/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-49838 (🔒)
GCVE (CVE): GCVE-0-2026-49838
GCVE (VulDB): GCVE-100-402274

Entryinfo

Created: 09/11/2026 00:12
Changes: 09/11/2026 00:12 (64)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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