---
cve: "CVE-2026-48983"
severity: "MEDIUM"
cvss: 5.8
epss: "11%"
vendor: "mcdope"
kev: false
exploited: false
published: "2026-06-18 20:16:14"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-13T19:56:08+02:00"
---

# CVE-2026-48983

> 5.8 MEDIUM · 🧪 PoC

## Beschreibung

pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, a symlink race condition exists in per-device and per-user pad directory creation. pam_usb uses a check-then-act pattern: it calls lstat() to test for existence and then calls mkdir() separately to create the directory. A local attacker can win the race between these calls by replacing the target path with a symlink to a directory they control. If successful, one-time pad files may be written to an attacker-controlled location, potentially exposing future pad values before use or disrupting authentication. This issue has been fixed in version 0.9.2.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- d4083e266b7e18e41e58b3392b5856941a3b5b1c (Commit)

## Referenzen

- <https://github.com/mcdope/pam_usb/security/advisories/GHSA-4j8q-67fq-3xc3>
- <https://github.com/mcdope/pam_usb/releases/tag/0.9.2>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-48983) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_