graphics/openexr*: security fix update to v3.4.15
"v3.4.15 fixes two memory issues when parsing IDManifests. Corrupt
or maliciously formed OpenEXR images could trigger excessive memory
allocation, but only in code which decodes the idmanifest attribute.
Other code is unaffected, even when handling files with idmanifest
attributes [...] CVEs have been requested for these issues."
https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.15
CVEs are not yet communicated.
Pull request: https://github.com/freebsd/freebsd-ports/pull/594
MFH: 2026Q3
PR: 297717
(cherry picked from commit e51c07e1f89545680baab090f517391137ca5834)