CVE-2025-64503 [BIGSLEEP-434615384] cups-filters 1.x: out of bounds write in pdftoraster
Crafted PDFs trigger an integer overflow in pdftoraster, causing an out-of-bounds write that may allow code execution or crashes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-64503?
CVE-2025-64503 is a medium-severity vulnerability in OpenPrinting cups-filters, published on 12 Nov 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
cups-filters contains backends, filters, and other software required to get the cups printing service working on operating systems other than macos. In cups-filters prior to 1.28.18, by crafting a PDF file with a large `MediaBox` value, an attacker can cause CUPS-Filter 1.x’s `pdftoraster` tool to write beyond the bounds of an array. First, a PDF with a large `MediaBox` width value causes `header.cupsWidth` to become large. Next, the calculation of `bytesPerLine = (header.cupsBitsPerPixel * header.cupsWidth + 7) / 8` overflows, resulting in a small value. Then, `lineBuf` is allocated with the small `bytesPerLine` size. Finally, `convertLineChunked` calls `writePixel8`, which attempts to write to `lineBuf` outside of its buffer size (out of bounds write). In libcupsfilters, the maintainers found the same `bytesPerLine` multiplication without overflow check, but the provided test case does not cause an overflow there, because the values are different. Commit 50d94ca0f2fa6177613c97c59791bde568631865 contains a patch, which is incorporated into cups-filters version 1.28.18.
Weakness: CWE-787
Which versions are affected by CVE-2025-64503?
It affects 2 products.
Products include Openprinting Cups-Filters, Openprinting Libcupsfilters.
How do I fix CVE-2025-64503?
Upgrade to a fixed version.
Is CVE-2025-64503 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-64503 exists.
Other vulnerabilities in OpenPrinting cups-filters
Sources
Also known as DEBIAN-CVE-2025-64503, GHSA-893j-2wr2-wrh9, UBUNTU-CVE-2025-64503.