{"id":"CVE-2026-19671","summary":"Improper handling of highly compressed data (data amplification) in CISA Malcolm","details":"Malcolm's upload-processing pipeline (scripts/safe-extract.py) enforces entry-count, nesting-depth, and total-uncompressed-byte limits when extracting container archives (zip/tar/rar/7z via libarchive), but those limits are not applied when the uploaded file is a single-stream compressed format (.gz, .bz2, .xz, .lzma, .lz) that isn't a .tar.*-style archive. Any authenticated user permitted to upload PCAP/log files can upload a small, highly compressible file (e.g. a gzip bomb) that decompresses to an effectively unbounded size on disk, exhausting the shared Docker volume used by OpenSearch, Logstash, Arkime, and Zeek, and disrupting the platform for all users.","aliases":["CVE-2026-19670","GHSA-f2v6-8cj4-mhr6"],"modified":"2026-08-20T03:30:36.188668458Z","published":"2026-08-18T19:11:58.230Z","database_specific":{"cna_assigner":"icscert","cwe_ids":["CWE-409"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19671.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19671.json"},{"type":"ADVISORY","url":"https://github.com/cisagov/Malcolm/security/advisories/GHSA-f2v6-8cj4-mhr6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-19671"},{"type":"ADVISORY","url":"https://www.cisa.gov/news-events/ics-advisories/icsa-26-230-01"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/cisagov/malcolm","events":[{"introduced":"0"},{"last_affected":"2c19ef04d85230634ac70cc68b8f418a0666afec"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"26.07.1"}],"source":"AFFECTED_FIELD"}}],"versions":["v26.07.1","v26.07.0","v26.06.1","v26.06.0","v26.05.2","v6.4.2","v6.4.1","v6.4.0","v5.2.4","v5.2.3","v5.2.2","v5.2.1","v3.0.1","v3.0.0","v2.6.1","v2.6.0","v2.5.0","v2.4.2","v2.4.1","v2.4.0.1","v2.4.0","v2.3.0","v2.2.1","v2.2.0","v2.1.1","v2.1.0","v2.0.6","v2.0.5","v2.0.4","v2.0.3","v2.0.2","v2.0.1","v2.0.0","v2.0.0-pre1","v1.8.1","v1.8.0","v1.7.2","v1.7.1a","v1.7.1","v1.7.0","v1.6.0","v1.5.2","v1.5.1","v1.5.0","v1.4.0","v1.3.1","v1.3.0","v1.2.2","v1.2.1","v1.2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-19671.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}