CVE-2026-41643Public exploitNetwork attack vector

Daemon crash via stale path-attribute index

Published May 7, 2026 · Updated May 7, 2026

Improper array-index validation in OSRG GoBGP before 4.3.0 allows remote attackers to crash the BGP daemon with a malformed UPDATE. UpdatePathAttrs4ByteAs deletes an invalid AS4_PATH that precedes AS_PATH but reuses the stale AS_PATH slice index, causing an out-of-range panic. A BGP peer, or a malformed route propagated through a transit provider, can stop the process and interrupt routing; no data access or modification is reported.

CVSS severity7.5
High
EPSS probability0.54%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper array-index validation in OSRG GoBGP before 4.3.0 allows remote attackers to crash the BGP daemon with a malformed UPDATE. UpdatePathAttrs4ByteAs deletes an invalid AS4_PATH that precedes AS_PATH but reuses the stale AS_PATH slice index, causing an out-of-range panic. A BGP peer, or a malformed route propagated through a transit provider, can stop the process and interrupt routing; no data access or modification is reported.

The record

CVE
CVE-2026-41643
Published
May 7, 2026
Updated
May 7, 2026
Vendor
GoBGP
Product
GoBGP
Classifications
CWE-129, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 7, 2026CVE publishedPublication date reported by the CVE source.
  2. May 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GoBGP · GoBGPversion=< 4.3.0

Published CVSS scores

7.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-129Improper Validation of Array Index
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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