{"id":"DEBIAN-CVE-2026-34379","details":"OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.2.0 to before 3.2.7, 3.3.9, and 3.4.9, a misaligned memory write vulnerability exists in LossyDctDecoder_execute() in src/lib/OpenEXRCore/internal_dwa_decoder.h:749. When decoding a DWA or DWAB-compressed EXR file containing a FLOAT-type channel, the decoder performs an in-place HALF→FLOAT conversion by casting an unaligned uint8_t * row pointer to float * and writing through it. Because the row buffer may not be 4-byte aligned, this constitutes undefined behavior under the C standard and crashes immediately on architectures that enforce alignment (ARM, RISC-V, etc.). On x86 it is silently tolerated at runtime but remains exploitable via compiler optimizations that assume aligned access. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.","modified":"2026-09-01T16:06:39.995829120Z","published":"2026-04-06T16:16:35.233Z","upstream":["CVE-2026-34379"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-34379"}],"affected":[{"package":{"name":"openexr","ecosystem":"Debian:12","purl":"pkg:deb/debian/openexr?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.13-1","3.1.13-2","3.1.5-5","3.1.5-5.1","3.1.5-5.1+hurd.1","3.4.14-0.1","3.4.6+ds-1","3.4.6+ds-2","3.4.6+ds-3","3.4.6+ds-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Debian:13","purl":"pkg:deb/debian/openexr?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.13-2","3.4.14-0.1","3.4.6+ds-1","3.4.6+ds-2","3.4.6+ds-3","3.4.6+ds-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Debian:14","purl":"pkg:deb/debian/openexr?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.14-0.1"}]}],"versions":["3.1.13-2","3.4.6+ds-1","3.4.6+ds-2","3.4.6+ds-3","3.4.6+ds-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-34379.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H"}]}