CVE-2026-44663
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedOpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. In versions 3.4.0 through 3.4.11, an integer overflow in ht_undo_impl() in src/lib/OpenEXRCore/internal_ht.cpp leads to a heap-buffer overflow when decoding a crafted HTJ2K-compressed EXR file. decode->channels[i].width (int32_t) is multiplied by bytes_per_element in 32-bit signed arithmetic. With large widths (e.g., >= 536870912 for FLOAT data), this overflows, producing a corrupted offset that is later used for pointer arithmetic and can cause a heap out-of-bounds write. The same unchecked multiplication pattern appears in two other HTJ2K paths (bytes-per-line accumulation and pixel-line pointer advancement). As with related CVE-2026-34378 through CVE-2026-34589 fixes in other codecs, validating only after the multiplication is too late because the value may already be overflowed. This issue has been fixed in version 3.4.12.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysisAn arithmetic operation produces a value too large for its type and wraps around to an unexpected — often tiny or negative — number. That miscalculated value then drives a memory allocation or a bounds check, opening the door to corruption. The fix is checked arithmetic and validating sizes before they're used.
General guidance for the integer overflow class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 3.4.0, < 3.4.12CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped3.4.12
OpenEXR 3.4.12
- Upgrade OpenEXR to version 3.4.12 or later. This can typically be done via your system's package manager (e.g., apt-get install libopenexr-dev, brew install openexr, or conda install openexr), or by building from source from the official repository.
- After upgrading, verify the version installed matches or exceeds 3.4.12 by running 'openexr-info' or checking the library version.
- Rebuild or recompile any applications that link against the OpenEXR library to ensure they use the updated version.
- If using OpenEXR in a custom application, verify that code paths handling HTJ2K-compressed files now correctly handle large dimensions without integer overflow.
Generated from the published advisory — verify against the referenced sources before acting.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-44663 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-44663 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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