Prevent load_time_zone() path traversal or arbitrary fopen - #353
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FileZoneInfoSource::Open() strips an optional file: prefix and then concatenates the remainder of the zone-name string under TZDIR (or uses it verbatim if absolute) with no canonicalisation or ".." rejection, then calls fopen(path, "rb"). An attacker-controlled zone name like "../../../../../../tmp/evil" escapes TZDIR. "file:/dev/stdin" or any FIFO blocks the calling thread indefinitely.
devbww
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Jul 18, 2026
devbww
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Jul 20, 2026
devbww
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Jul 20, 2026
mkruskal-google
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Jul 20, 2026
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FileZoneInfoSource::Open() strips an optional file: prefix and then concatenates the remainder of the zone-name string under TZDIR (or uses it verbatim if absolute) with no canonicalisation or ".." rejection, then calls fopen(path, "rb"). An attacker-controlled zone name like "../../../../../../tmp/evil" escapes TZDIR. "file:/dev/stdin" or any FIFO blocks the calling thread indefinitely.