CVE-2026-48983

MEDIUMPre-NVD 5.85.8—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 100% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.8
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.8Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
5.8
EG Score
5.8(medium)
EPSS
0.3%
KEV
Not listed

Published

June 18, 2026

Last Modified

June 22, 2026

Advisory Details (2)

Auto-updated Jun 18, 2026
Patch available. Sources: github_release, github.
github Patch Available

TOCTOU race condition in pad directory creation allows symlink substitution · Advisory · mcdope/pam_usb · GitHub

https://github.com/mcdope/pam_usb/security/advisories/GHSA-4j8q-67fq-3xc3
github_release Patch Available

0.9.2 — Security Hardening Release

Patch available: mcdope/pam_usb 0.9.2

https://github.com/mcdope/pam_usb/releases/tag/0.9.2

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 11× in last 7d / 41× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-12 05:46 UTCEPSS rescore
  2. 2026-07-11 15:05 UTCEG score recompute
  3. 2026-07-11 08:27 UTCEPSS rescore
  4. 2026-07-10 14:29 UTCEG score recompute
  5. 2026-07-09 19:10 UTCEPSS rescore
  6. 2026-07-09 13:43 UTCEG score recompute
  7. 2026-07-08 15:16 UTCEPSS rescore
  8. 2026-07-08 13:06 UTCEG score recompute
  9. 2026-07-07 13:46 UTCEPSS rescore
  10. 2026-07-07 11:14 UTCEG score recompute
  11. 2026-07-06 09:39 UTCEG score recompute
  12. 2026-07-05 08:27 UTCEG score recompute
  13. 2026-07-04 07:52 UTCEG score recompute
  14. 2026-07-04 06:31 UTCEPSS rescore
  15. 2026-07-03 06:04 UTCEG score recompute
  16. 2026-07-02 05:27 UTCEG score recompute
  17. 2026-07-01 15:07 UTCEPSS rescore
  18. 2026-07-01 04:52 UTCEG score recompute
  19. 2026-06-30 23:22 UTCEPSS rescore
  20. 2026-06-30 04:15 UTCEG score recompute
  21. 2026-06-29 14:06 UTCEPSS rescore
  22. 2026-06-29 14:06 UTCEPSS rescore
  23. 2026-06-29 03:39 UTCEG score recompute
  24. 2026-06-28 14:07 UTCEPSS rescore
  25. 2026-06-28 04:56 UTCEPSS rescore
Show 16 more
  1. 2026-06-28 04:56 UTCEPSS rescore
  2. 2026-06-28 03:03 UTCEG score recompute
  3. 2026-06-27 03:08 UTCEPSS rescore
  4. 2026-06-27 02:27 UTCEG score recompute
  5. 2026-06-26 01:51 UTCEG score recompute
  6. 2026-06-25 13:49 UTCEPSS rescore
  7. 2026-06-25 01:16 UTCEG score recompute
  8. 2026-06-24 00:40 UTCEG score recompute
  9. 2026-06-23 21:33 UTCEPSS rescore
  10. 2026-06-23 21:33 UTCEPSS rescore
  11. 2026-06-22 23:55 UTCEG score recompute
  12. 2026-06-21 23:15 UTCEG score recompute
  13. 2026-06-20 22:36 UTCEG score recompute
  14. 2026-06-19 21:59 UTCEG score recompute
  15. 2026-06-18 21:24 UTCEG score recompute
  16. 2026-06-18 21:23 UTCNVD updatefirst tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-48983?
CVE-2026-48983 is a medium vulnerability published on June 18, 2026. pamusb 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. pamusb uses a check-then-act pattern: it calls lstat() to test for existence and then calls mkdir()…
When was CVE-2026-48983 disclosed?
CVE-2026-48983 was first published in the National Vulnerability Database on June 18, 2026, with the most recent update on June 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48983 actively exploited?
CVE-2026-48983 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-48983?
CVE-2026-48983 has a CVSS v3 base score of 5.8 (NVD).
How do I remediate CVE-2026-48983?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48983, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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