CVE-2026-53503 (GCVE-0-2026-53503)

Vulnerability from cvelistv5 – Published: 2026-07-31 18:54 – Updated: 2026-07-31 21:39
VLAI
Title
Thumbor convolution filter allows divide-by-zero in C extension leading to remote DoS
Summary
Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:convolution(<matrix>, <columns>, <should_normalize>) filter passes the user-controlled <columns> value to a C extension (thumbor/ext/filters/_convolution.c) where it is used as a divisor (for % and /) without validating columns > 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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-31 20:14 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7838 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
thumbor thumbor Affected: < 7.8.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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