CVE-2026-34378
OpenEXR has a signed integer overflow in generic_unpack() when parsing EXR files with crafted negative dataWindow.min.x
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
OpenEXR has a signed integer overflow in generic_unpack() when parsing EXR files with crafted negative dataWindow.min.x
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-190
- Updated
- 2026-11-02
EUVDEUVD-2026-19303
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
EUVD-2026-19303- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
NVD
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-190
- Updated
- 2026-11-02
OSVALPINE-CVE-2026-34378
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
ALPINE-CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
OSVBELL-CVE-2026-34378
- Record
BELL-CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSV
OpenEXR has a signed integer overflow in generic_unpack() when parsing EXR files with crafted negative dataWindow.min.x
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Weakness
- CWE-190
- Updated
- 2026-11-02
Show 6 moreShow less
OSVDEBIAN-CVE-2026-34378
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
DEBIAN-CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVJLSEC-2026-142
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
JLSEC-2026-142- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-34378
OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. From 3.4.0 to before 3.4.9, a missing bounds check on the dataWindow attribute in EXR file headers allows an attacker to trigger a signed integer overflow in generic_unpack(). By setting dataWindow.min.x to a large negative value, OpenEXRCore computes an enormous image width, which is later used in a signed integer multiplication that overflows, causing the process to terminate with SIGILL via UBSan. This vulnerability is fixed in 3.4.9.
- Record
UBUNTU-CVE-2026-34378- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVCLSA-2026-1785335342 No score
openexr: Fix of 2 CVEs
- CVE-2026-34380: fix signed 32-bit integer overflow in the PXR24 decoder bounds check, where (uint64_t) (w * 3) wrapped to a small positive value and allowed an out-of-bounds write through dout
- CVE-2026-34378: fix signed 32-bit integer overflow in srcbuffer pointer arithmetic in the unpack_* routines, reached via an oversized dataWindow width
- Record
CLSA-2026-1785335342- Updated
- 2026-11-02
OSVCLSA-2026-1785425808 No score
openexr: Fix of 2 CVEs
- CVE-2026-34380: fix signed 32-bit integer overflow in the PXR24 decoder bounds check, where (uint64_t) (w * 3) wrapped to a small positive value and allowed an out-of-bounds write through dout
- CVE-2026-34378: fix signed 32-bit integer overflow in srcbuffer pointer arithmetic in the unpack_* routines, reached via an oversized dataWindow width
- Record
CLSA-2026-1785425808- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:10505-1 No score
libIex-3_4-33-3.4.9-1.1 on GA media
These are all security issues fixed in the libIex-3_4-33-3.4.9-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:10505-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
openexrAlpine:v3.22 |
3.4.0 up to 3.3.11-r0 | 3.3.11-r0 |
openexrAlpine:v3.23 |
3.4.0 up to 3.4.13-r0 | 3.4.13-r0 |
openexrAlpine:v3.24 |
3.4.0 up to 3.4.10-r0 | 3.4.10-r0 |
openexrAlpaquita:stream |
3.4.4-r0 up to 3.4.9-r0 | 3.4.9-r0 |
openexrTuxCare:AlmaLinux:9.2 |
before 3.1.1-3.el9.tuxcare.els9 | 3.1.1-3.el9.tuxcare.els9 |
openexr-develTuxCare:AlmaLinux:9.2 |
before 3.1.1-3.el9.tuxcare.els9 | 3.1.1-3.el9.tuxcare.els9 |
openexr-libsTuxCare:AlmaLinux:9.2 |
before 3.1.1-3.el9.tuxcare.els9 | 3.1.1-3.el9.tuxcare.els9 |
openexrTuxCare:AlmaLinux:9.6 |
before 3.1.1-3.el9.tuxcare.els9 | 3.1.1-3.el9.tuxcare.els9 |
openexr-develTuxCare:AlmaLinux:9.6 |
before 3.1.1-3.el9.tuxcare.els9 | 3.1.1-3.el9.tuxcare.els9 |
openexr-libsTuxCare:AlmaLinux:9.6 |
before 3.1.1-3.el9.tuxcare.els9 | 3.1.1-3.el9.tuxcare.els9 |
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| Package | Affected | Fixed |
|---|---|---|
openexrDebian:14 |
before 3.4.14-0.1, plus listed versions 3.1.13-23.4.6+ds-13.4.6+ds-23.4.6+ds-33.4.6+ds-4 |
3.4.14-0.1 |
OpenEXR_jllJulia |
3.4.4+0 up to 3.4.9+0 | 3.4.9+0 |
openexrUbuntu:26.10 |
All versions, plus listed versions 3.1.13-2build13.4.6+ds-4ubuntu3 |
None known |
openexropenSUSE:Tumbleweed |
before 3.4.9-1.1 | 3.4.9-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | OSV | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-34378 is a medium vulnerability (CVSS 6.5) in Academysoftwarefoundation Openexr, published April 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.27%, the 19th percentile. Fixed in openexr 3.3.11-r0.
References
github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-v76p-4qvv-vh4g
security.alpinelinux.org/vuln/CVE-2026-34378
docs.bell-sw.com/security/cves/CVE-2026-34378
errata.tuxcare.com/els_os/almalinux9.2esu/CLSA-2026-1785335342.html
nvd.nist.gov/vuln/detail/CVE-2026-34378
Show 17 moreShow less
security-tracker.debian.org/tracker/CVE-2026-34378
ubuntu.com/security/CVE-2026-34378
cve.org/CVERecord?id=CVE-2026-34378
suse.com/security/cve/CVE-2026-34378