{"id":"ALPINE-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":"2026-11-03T06:32:54.884428019Z","published":"2026-04-06T16:16:35.233Z","upstream":["CVE-2026-34379"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2026-34379"}],"affected":[{"package":{"name":"openexr","ecosystem":"Alpine:v3.22","purl":"pkg:apk/alpine/openexr?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.2.0"},{"fixed":"3.3.11-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/openexr?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.2.0"},{"fixed":"3.4.13-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/openexr?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.2.0"},{"fixed":"3.4.10-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-34379.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H"}]}