Raw vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XSummary
CVE-2026-34588 is a high-severity Out-of-bounds Read (CWE-125) vulnerability in Openexr Openexr. Its CVSS base score is 8.6 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 39th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-34588 is an integer overflow vulnerability in the OpenEXR library, which provides the specification and reference implementation for the EXR image file format used in the motion picture industry. The issue affects versions from 3.1.0 up to but not including 3.2.7, 3.3.9, and 3.4.9. Specifically, the function internal_exr_undo_piz() performs signed 32-bit arithmetic to advance a working wavelet pointer using values nx, ny, and wcount, which are of type int. A crafted EXR file can trigger an overflow, causing the pointer to wrap and point to an incorrect address. Since the wavelet decode path operates in place, this results in out-of-bounds reads and writes. The vulnerability is associated with CWE-125 (Out-of-bounds Read), CWE-190 (Integer Overflow or Wraparound), and CWE-787 (Out-of-bounds Write), and carries a CVSS v3.1 base score of 7.8.
An attacker with local access and low privileges (PR:L) can exploit this vulnerability by supplying a maliciously crafted EXR file to an affected OpenEXR instance, with low attack complexity and no user interaction required. Successful exploitation leads to high-impact confidentiality, integrity, and availability consequences (C:H/I:H/A:H), potentially allowing arbitrary code execution, data corruption, or denial of service through out-of-bounds memory access in the decoding process.
Mitigation is available via patches released by the Academy Software Foundation. Vendors and users should update to OpenEXR version 3.2.7, 3.3.9, or 3.4.9, as detailed in the corresponding GitHub release notes and the security advisory at GHSA-588r-cr5c-w6hf.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-19347
Vulnerability Data
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.1.0 to before 3.2.7, 3.3.9, and 3.4.9, internal_exr_undo_piz() advances the working wavelet pointer with signed 32-bit arithmetic. Because…
more
nx, ny, and wcount are int, a crafted EXR file can make this product overflow and wrap. The next channel then decodes from an incorrect address. The wavelet decode path operates in place, so this yields both out-of-bounds reads and out-of-bounds writes. This vulnerability is fixed in 3.2.7, 3.3.9, and 3.4.9.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
—
V5.2.6
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation directly finds out-of-bounds read flaws through static analysis, fuzzing, and dynamic bounds checks.
Requiring documented secure-development standards and tools can mandate bounds-checked coding practices that avoid the weakness.
Secure engineering principles require bounds checking and memory-safe constructs that stop out-of-bounds reads from being introduced.
Process isolation confines the effects of an out-of-bounds read to the compromised process.
Input validation rejects malformed indices or lengths that would otherwise cause reads outside buffer bounds.
Memory-protection mechanisms limit the exploitability and blast radius of a successful out-of-bounds write.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.
Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.
Routine patching replaces vulnerable code containing out-of-bounds read flaws.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development and acceptance includes fuzzing and static analysis that detect out-of-bounds read defects before release.
Logging can record evidence of an out-of-bounds read but does not prevent the weakness itself.
Secure development life cycle mandates input validation and bounds checking that directly prevent out-of-bounds reads.
Application security requirements include explicit bounds and memory-safety specifications that mitigate buffer over-reads.
Secure system architecture and engineering principles require memory-safe design patterns and runtime protections against out-of-bounds access.
Secure coding standards explicitly forbid unsafe pointer arithmetic and mandate bounds-checked reads, eliminating CWE-125.