CVE-2026-41643 | GoBGP: Remote Denial of Service (Panic) in UpdatePathAttrs4ByteAs via Malformed BGP UPDATE

Exp

GoBGP is an open source Border Gateway Protocol (BGP) implementation in the Go Programming Language. Prior to version 4.3.0, a remote Denial of Service (DoS) vulnerability exists in GoBGP where a malformed BGP UPDATE message can trigger a runtime error: index out of range panic. This occurs during the processing of 4-byte AS attributes when the message structure causes an internal slice index shift that is not properly handled. This issue has been patched in version 4.3.0.

Published: 2026-05-07 Last update: 2026-05-07 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-41643 is rated Exploit Available (50.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.05%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-41643

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-41643

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-08 0.05% 0.05% +0.00%
2 2026-05-22 0.15% 0.05% -0.11%
3 2026-05-13 — 0.15% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-41643

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-41643

GitHub Security Advisory for CVE-2026-41643

GHSA-8rxh-r2p6-7f2q · Severity: high · Ecosystem: go — GoBGP has Remote Denial of Service (Panic) in UpdatePathAttrs4ByteAs via Malformed BGP UPDATE

OS Trackers for CVE-2026-41643

vendor priority summary link
debian not yet assigned CVE-2026-41643 not yet assigned priority: Debian including 1 source packages (gobgp), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-41643
ubuntu medium CVE-2026-41643 medium priority: Ubuntu including 1 source packages (gobgp), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): needs-triage 7. https://ubuntu.com/security/CVE-2026-41643

Affected software / configurations for CVE-2026-41643

Vendor Product Version Raw CPE
osrg gobgp < 4.3.0 cpe:2.3:a:osrg:gobgp:*:*:*:*:*:*:*:*

References for CVE-2026-41643

cvelogic Threat Intelligence