Bird-lg-go has a Fatal Out-of-Memory (OOM) Denial of Service via Unbounded JSON Decoding

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-45047: 0.44% estimated exploitation activity in the next 30 days; percentile 38.40 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The apiHandler (and similarly webHandlerTelegramBot) processes user-provided JSON payloads by directly using json.NewDecoder(r.Body).Decode(&request) without restricting the maximum read size. An unauthenticated remote attacker can stream an extremely large, endless JSON payload (e.g., several Gigabytes of padding) over a single TCP connection. Because Go's JSON decoder attempts to allocate memory for the entire parsed structure, this rapidly exhausts the host's physical RAM or container limits, leading to an unrecoverable fatal error: runtime: out of memory. This causes the Linux OOM Killer to instantly terminate the entire bird-lg-go daemon, resulting in a severe Remote Denial of Service (RDoS). Details In api.go: go func apiHandler(w http.ResponseWriter, r http.Request) { var request apiRequest // VULNERABILITY: No http.MaxBytesReader protection before JSON decode err := json.NewDecoder(r.Body).Decode(&request) // ...

Published by the source

11 May 2026, 16:17 UTC

Last modified by the source

8 Jun 2026, 23:49 UTC

Source last checked

26 Oct 2026, 15:23 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-39qr-rc93-vhqm

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-45047

Advisory: Bird-lg-go has a Fatal Out-of-Memory (OOM) Denial of Service via Unbounded JSON Decoding
IDs: CVE-2026-45047, GHSA-39qr-rc93-vhqm
Record: https://patchnext.com/advisories/cve-2026-45047 (revision 1, source checked 26 Oct 2026, 15:23 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/xddxdd/bird-lg-go 0.0.0-20260507060110-0ff87024cb9e. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/xddxdd/bird-lg-go: affected < 0.0.0-20260507060110-0ff87024cb9e; fixed in 0.0.0-20260507060110-0ff87024cb9e

## Suggested inspection (read-only)
- Go github.com/xddxdd/bird-lg-go: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/xddxdd/bird-lg-go.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-39qr-rc93-vhqm (GitHub-reviewed advisory GHSA-39qr-rc93-vhqm lists affected ranges: Go github.com/xddxdd/bird-lg-go >=0 <0.0.0-20260507060110-0ff87024cb9e)

Commands are suggestions: review each one before running it.