CVE-2026-103436

apcupsd through 3.14.14 discloses uninitialized stack memory in getupsvar() in src/cgi/upsfetch.c (used by upsstats.cgi, multimon.cgi, and upsfstats.cgi. On the single-field path, when the matched STATUS line has fewer than three whitespace-separated tokens, sscanf("%*s %*s %s", answer) performs no assignment but the function returns success, and thus the caller prints the uninitialized destination buffer into the HTTP response.

CVSS 3.1

3.7CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS

0.3% chance of exploitation in the next 30 days; higher than 21% of CVEs (scores of 2026-10-25)

CWE

CWE-457

Published

2026-09-30

Modified

2026-10-02

Record from

the NVD, synced 2026-10-19

References

• https://bugzilla.redhat.com/show_bug.cgi?id=2493140
• https://github.com/therealbstern/apcupsd/blob/224d19d5faa508d04267f6135fe53d50800550de/src/cgi/upsfetch.c#L240
• https://sourceforge.net/projects/apcupsd/

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