The JPXStream::init function in Poppler 0.78.0 and earlier doesn't check for negative values of stream length, leading to an Integer Overflow, thereby making it possible to allocate a large memory chunk on the heap, with a size controlled by an attacker, as demonstrated by pdftocairo.
Severity
CVSS 3.1
6.5 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
1.9% chance of exploitation in the next 30 days; higher than 79% of CVEs (scores of 2026-10-31)