---
cve: "CVE-2026-72057"
severity: "HIGH"
cvss: 8.2
epss: "55%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-08-15 06:21:15"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-11T02:30:58+02:00"
---

# CVE-2026-72057

> 8.2 HIGH

## Beschreibung

In the Linux kernel, the following vulnerability has been resolved:

net/sched: act_ct: preserve tc_skb_cb across defragmentation

tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving
and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases
the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through
act_ct therefore loses qdisc metadata such as pkt_segs and can trigger
WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled.

Save and restore the full tc_skb_cb around nf_ct_handle_fragments(),
matching the pattern used by ovs_ct_handle_fragments().

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Keine | good |
| I Integrität | Gering | warn |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- Kernel ≥ 5.15.217
- Kernel ≥ 6.1.184
- Kernel ≥ 6.12.97
- Kernel ≥ 6.18.40
- Kernel ≥ 7.1.5

## Referenzen

- <https://git.kernel.org/stable/c/2400c4b05d58834b994500a9eec90a37db44187c>
- <https://git.kernel.org/stable/c/5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac>
- <https://git.kernel.org/stable/c/b3d835407846134b0d54637c0281b39bebef831d>
- <https://git.kernel.org/stable/c/f7f45ceb855d9ba1cba594fb3f383255f7013fad>
- <https://git.kernel.org/stable/c/9092e15defbe6c7bc241c306093ca9d358a578e7>
- <https://git.kernel.org/stable/c/67d6b00a54446c008f52cf70fc0c2ad0c712f85d>
- <https://git.kernel.org/stable/c/fb080b6f54835d5d4d11ce3122800e6f0f6689e6>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-72057) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_