{"id":"UBUNTU-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is fixed in 3.2.7, 3.3.9, and 3.4.9.","modified":"2026-05-07T14:02:37.903396Z","published":"2026-04-06T16:16:00Z","withdrawn":"2026-05-07T12:28:07Z","upstream":["CVE-2026-34379"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-34379"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-34379"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-w88v-vqhq-5p24"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/pull/2324"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/commit/3ad9b29430f9c2599dad113e1efe619a6ec7ba67"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/commit/d32ffe9d3727c0474b63e91556baf61ced3d89e0"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/commit/76af7d7508819a477f2cbce808ee975da8053ce3"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.2.7"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.3.9"},{"type":"REPORT","url":"https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.9"}],"affected":[{"package":{"name":"openexr","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/openexr@2.2.0-10ubuntu2.6+esm3?arch=source&distro=esm-infra/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.2.0-1ubuntu3","2.2.0-7ubuntu1","2.2.0-9ubuntu1","2.2.0-10ubuntu2","2.2.0-10ubuntu2.1","2.2.0-10ubuntu2.2","2.2.0-10ubuntu2.3","2.2.0-10ubuntu2.4","2.2.0-10ubuntu2.6","2.2.0-10ubuntu2.6+esm1","2.2.0-10ubuntu2.6+esm2","2.2.0-10ubuntu2.6+esm3"],"ecosystem_specific":{"binaries":[{"binary_name":"libopenexr22","binary_version":"2.2.0-10ubuntu2.6+esm3"},{"binary_name":"openexr","binary_version":"2.2.0-10ubuntu2.6+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/openexr@2.2.0-11.1ubuntu1.9?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.2.0-11ubuntu1","2.2.0-11.1ubuntu1","2.2.0-11.1ubuntu1.1","2.2.0-11.1ubuntu1.2","2.2.0-11.1ubuntu1.3","2.2.0-11.1ubuntu1.4","2.2.0-11.1ubuntu1.6","2.2.0-11.1ubuntu1.7","2.2.0-11.1ubuntu1.8","2.2.0-11.1ubuntu1.9"],"ecosystem_specific":{"binaries":[{"binary_name":"libopenexr22","binary_version":"2.2.0-11.1ubuntu1.9"},{"binary_name":"openexr","binary_version":"2.2.0-11.1ubuntu1.9"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/openexr@2.3.0-6ubuntu0.5+esm1?arch=source&distro=esm-apps/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.2.1-4.1ubuntu1","2.3.0-6","2.3.0-6build1","2.3.0-6ubuntu0.1","2.3.0-6ubuntu0.2","2.3.0-6ubuntu0.3","2.3.0-6ubuntu0.5","2.3.0-6ubuntu0.5+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libopenexr24","binary_version":"2.3.0-6ubuntu0.5+esm1"},{"binary_name":"openexr","binary_version":"2.3.0-6ubuntu0.5+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/openexr@2.5.7-1ubuntu0.1~esm1?arch=source&distro=esm-apps/jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.5.4-2","2.5.7-1","2.5.7-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.5.7-1ubuntu0.1~esm1","binary_name":"libopenexr25"},{"binary_name":"openexr","binary_version":"2.5.7-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/openexr@3.1.5-5.1build3?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.5-5.1","3.1.5-5.1build1","3.1.5-5.1build2","3.1.5-5.1build3"],"ecosystem_specific":{"binaries":[{"binary_name":"libopenexr-3-1-30","binary_version":"3.1.5-5.1build3"},{"binary_name":"openexr","binary_version":"3.1.5-5.1build3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34379.json"}},{"package":{"name":"openexr","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/openexr@3.1.13-2?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.13-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libopenexr-3-1-30","binary_version":"3.1.13-2"},{"binary_name":"openexr","binary_version":"3.1.13-2"}]},"database_specific":{"source":"https://github.com/canon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