---
cve: "CVE-2026-34219"
severity: "HIGH"
cvss: 8.2
epss: "40%"
vendor: "libp2p"
kev: false
exploited: false
published: "2026-03-31 16:16:31"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-04T02:01:53+02:00"
---

# CVE-2026-34219

> 8.2 HIGH · 🧪 PoC

## Beschreibung

libp2p-rust is the official rust language Implementation of the libp2p networking stack. Prior to version 0.49.4, the Rust libp2p Gossipsub implementation contains a remotely reachable panic in backoff expiry handling. After a peer sends a crafted PRUNE control message with an attacker-controlled, near-maximum backoff value, the value is accepted and stored as an Instant near the representable upper bound. On a later heartbeat, the implementation performs unchecked Instant + Duration arithmetic (backoff_time + slack), which can overflow and panic with: overflow when adding duration to instant. This issue is reachable from any Gossipsub peer over normal TCP + Noise + mplex/yamux connectivity and requires no further authentication beyond becoming a protocol peer. This issue has been patched in version 0.49.4.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Referenzen

- <https://github.com/libp2p/rust-libp2p/security/advisories/GHSA-xqmp-fxgv-xvq5>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-34219) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_