{"id":"DEBIAN-CVE-2026-53503","details":"Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:convolution(\u003cmatrix\u003e, \u003ccolumns\u003e, \u003cshould_normalize\u003e) filter passes the user-controlled \u003ccolumns\u003e value to a C extension (thumbor/ext/filters/_convolution.c) where it is used as a divisor (for % and /) without validating columns \u003e 0. When columns=0, the C code triggers undefined behavior; on x86_64 this reliably results in a fatal divide-by-zero trap (SIGFPE) and crashes the Thumbor process, causing a remote denial of service. This issue is fixed in 7.8.0.","modified":"2026-09-09T08:47:32.269565849Z","published":"2026-07-31T19:17:09.737Z","upstream":["CVE-2026-53503"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-53503"}],"affected":[{"package":{"name":"thumbor","ecosystem":"Debian:14","purl":"pkg:deb/debian/thumbor?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.8.0-1"}]}],"versions":["6.3.2-3","6.3.2-4","6.5.1-1","6.5.1-2","6.5.1-3","6.5.1-4","6.5.1-5","6.5.1-6","6.5.1-7","6.7.0-1","7.7.7-1","7.7.7-2","7.7.7-3","7.7.7-4","7.7.7-5","7.7.7-6"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-53503.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}