{"id":"CVE-2026-48982","state":"PUBLISHED","title":"pam_usb: Missing O_EXCL on pad temp file creation allows concurrent update race","description":"pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, when updating a one-time pad file, a temporary file is created using open() without the O_EXCL flag. Without O_EXCL, the create operation is not atomic: two concurrent processes racing to update the same pad may both succeed in opening the file, with the second write silently overwriting the first. The one-time pad is the core replay-prevention mechanism of pam_usb. A successful race could result in the stored pad value diverging from what either process expected, potentially causing authentication failures or, in a precisely timed attack, creating a window for pad reuse. This issue has been fixed in version 0.9.2.","publishedAt":"2026-06-18T19:01:08.766Z","updatedAt":"2026-06-22T17:16:39.634Z","severity":{"score":5.8,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["mcdope pam_usb"],"affected":[{"vendor":"mcdope","product":"pam_usb","versions":[{"version":"< 0.9.2","status":"affected"}]}],"references":["https://github.com/mcdope/pam_usb/security/advisories/GHSA-hxh6-9574-5vp6","https://github.com/mcdope/pam_usb/releases/tag/0.9.2"],"weaknesses":["CWE-362"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/48xxx/CVE-2026-48982.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-48982","state":"PUBLISHED","datePublished":"2026-06-18T19:01:08.766Z","dateUpdated":"2026-06-22T17:16:39.634Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-26T23:26:07.974Z"},"containers":{"cna":{"title":"pam_usb: Missing O_EXCL on pad temp file creation allows concurrent update race","descriptions":[{"lang":"en","value":"pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, when updating a one-time pad file, a temporary file is created using open() without the O_EXCL flag. Without O_EXCL, the create operation is not atomic: two concurrent processes racing to update the same pad may both succeed in opening the file, with the second write silently overwriting the first. The one-time pad is the core replay-prevention mechanism of pam_usb. A successful race could result in the stored pad value diverging from what either process expected, potentially causing authentication failures or, in a precisely timed attack, creating a window for pad reuse. This issue has been fixed in version 0.9.2."}],"affected":[{"vendor":"mcdope","product":"pam_usb","versions":[{"version":"< 0.9.2","status":"affected"}]}],"references":[{"url":"https://github.com/mcdope/pam_usb/security/advisories/GHSA-hxh6-9574-5vp6","name":"https://github.com/mcdope/pam_usb/security/advisories/GHSA-hxh6-9574-5vp6","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/mcdope/pam_usb/releases/tag/0.9.2","name":"https://github.com/mcdope/pam_usb/releases/tag/0.9.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"LOCAL","availabilityImpact":"LOW","baseScore":5.8,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-362","lang":"en","description":"CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-18T19:01:08.766Z"},"source":{"advisory":"GHSA-hxh6-9574-5vp6","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-22T15:35:08.355851Z","id":"CVE-2026-48982","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-22T17:16:39.634Z"}}]}}}