CVE-2026-48984
On a system where a use-after-free condition exists, or where a heap inspection primitive becomes available, this could allow recovery of pad values or other authentication material from freed memory regions.
Does this matter?
Lower severity and a low EPSS score (0.15%). Track it; it rarely justifies an emergency change on its own.
Description
pam_usb provides hardware authentication for Linux using ordinary removable media. In versions 0.9.1 and below, the xfree() memory release helper in calls free() without first zeroing the buffer contents, releasing heap-allocated buffers containing sensitive data — including one-time pad bytes read from disk — without clearing, leaving the sensitive content in freed heap memory until it happens to be overwritten by a subsequent allocation. On a system where a use-after-free condition exists, or where a heap inspection primitive becomes available, this could allow recovery of pad values or other authentication material from freed memory regions. This is a defence-in-depth requirement consistent with prior hardening work in this codebase (GHSA-vx6f-rrqr-j87c applied explicit_bzero to some pad paths; this issue generalises the pattern to the central deallocation helper).
- CVSS 3.1
- 4.7 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.15% probability · 4th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-14, CWE-226
- Source
- security-advisories@github.com
EPSS 0.1% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.