CVE-2025-43972Network attack vector

Remote service crash via truncated FlowSpec redirect

Published Apr 21, 2025 · Updated Apr 21, 2025

Improper input-length validation in GoBGP before 3.35.0 allows remote attackers to crash the BGP process with a malformed FlowSpec update. In parseGenericTransitiveExperimentalExtended, the IPv6 redirect-community case slices bytes 2 through 20 after checking only that eight bytes are present. Reachability requires a BGP session with the FlowSpec address family enabled; the resulting out-of-bounds slice terminates the process and interrupts routing service.

CVSS severity7.5
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input-length validation in GoBGP before 3.35.0 allows remote attackers to crash the BGP process with a malformed FlowSpec update. In parseGenericTransitiveExperimentalExtended, the IPv6 redirect-community case slices bytes 2 through 20 after checking only that eight bytes are present. Reachability requires a BGP session with the FlowSpec address family enabled; the resulting out-of-bounds slice terminates the process and interrupts routing service.

The record

CVE
CVE-2025-43972
Published
Apr 21, 2025
Updated
Apr 21, 2025
Vendor
GoBGP
Product
GoBGP
Classifications
CWE-1284, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 21, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2025Record 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=0 <3.35.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GoBGP · GoBGPversion=0 <3.35.0

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
6.8MITRECVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-1284Improper Validation of Specified Quantity in Input
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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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