{"cve":{"cve_id":"CVE-2026-39886","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00302,"epss_percentile":0.21691,"epss_as_of":"2026-06-23","description":"OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. Versions 3.4.0 through 3.4.9 have a signed integer overflow vulnerability in OpenEXR's HTJ2K (High-Throughput JPEG 2000) decompression path. The `ht_undo_impl()` function in `src/lib/OpenEXRCore/internal_ht.cpp` accumulates a bytes-per-line value (`bpl`) using a 32-bit signed integer with no overflow guard. A crafted EXR file with 16,385 FLOAT channels at the HTJ2K maximum width of 32,767 causes `bpl` to overflow `INT_MAX`, producing undefined behavior confirmed by UBSan. On an\nallocator-permissive host where the required ~64 GB allocation succeeds, the wrapped negative `bpl` value would subsequently be used as a per-scanline pointer advance, which would produce a heap out-of-bounds write. On a memory-constrained host, the allocation fails before `ht_undo_impl()` is entered. This is the second distinct integer overflow in `ht_undo_impl()`. CVE-2026-34545 addressed a different overflow in the same function — the `int16_t p` pixel-loop counter at line ~302 that overflows when iterating over channels whose `width` exceeds 32,767. The CVE-2026-34545 fix did not touch the `int bpl` accumulator at line 211, which is the subject of this advisory. The `bpl` accumulator was also not addressed by any of the 8 advisories in the 2026-04-05 v3.4.9 release batch. This finding is structurally identical to CVE-2026-34588 (PIZ `wcount*nx` overflow in `internal_piz.c`) and should be remediated with the same pattern. The CVE-2026-34588 fix did not touch `internal_ht.cpp`. Version 3.4.10 contains a remediation that addresses the vulnerability in `internal_ht.cpp`.","published_at":"2026-04-21T01:27:01.371000Z","last_modified_at":null,"cvss_v3_score":5.3,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","cvss_v3_severity":"MEDIUM","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-190"],"nvd_references":["https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-r3mr-mx8q-jcw5","https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.10"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:30:09.771414Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"L","value_label":"Low"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"academysoftwarefoundation","vendor_name":"AcademySoftwareFoundation","product_slug":"openexr","product_name":"openexr","version_start":">= 3.4.0, < 3.4.10","version_start_inclusive":true,"version_end":">= 3.4.0, < 3.4.10","version_end_inclusive":true,"cpe23_uri":"cve5:academysoftwarefoundation:openexr:>= 3.4.0, < 3.4.10:>= 3.4.0, < 3.4.10"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-r3mr-mx8q-jcw5","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/AcademySoftwareFoundation/openexr/releases/tag/v3.4.10","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-04-21T01:27:01.371000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:53:39.415886Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:53:39.415886Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:53:39.415886Z","label":"CVSS score revised","source":"cvelistv5"}]}