OpenEXR provides the specification and reference implementation of the EXR file format, an image storage format for the motion picture industry. In versions 3.3.0 through 3.3.6 and 3.4.0 through 3.4.4, a heap-buffer-overflow (OOB read) occurs in the istream_nonparallel_read function in ImfContextInit.cpp when parsing a malformed EXR file through a memory-mapped IStream. A signed integer subtraction produces a negative value that is implicitly converted to size_t, resulting in a massive length being passed to memcpy. Versions 3.3.7 and 3.4.5 contain a patch.
CVE-2026-26981
This medium-severity CVE scores 6.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 58% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 6.5(medium)
- EG Risk
- 34(Track)EG Risk 34/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation1% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 43%
- KEV
- Not listed
Published
February 24, 2026
Last Modified
June 17, 2026
Advisory Details (3)
Auto-updated Aug 4, 2026Heap-buffer-overflow via signed integer underflow in ImfContextInit.cpp · Advisory · AcademySoftwareFoundation/openexr · GitHub
https://github.com/AcademySoftwareFoundation/openexr/security/advisories/GHSA-q6vj-wxvf-5m8ccommit d2be382758ad (AcademySoftwareFoundation/openexr)
Patch available: AcademySoftwareFoundation/openexr v3.3.7 (contains commit d2be382758ad)
https://github.com/AcademySoftwareFoundation/openexr/commit/d2be382758adc3e9ab83a3de35138ec28d93ebd8commit 6bb2ddf10685 (AcademySoftwareFoundation/openexr)
Patch available: AcademySoftwareFoundation/openexr v3.4.5 (contains commit 6bb2ddf10685)
https://github.com/AcademySoftwareFoundation/openexr/commit/6bb2ddf1068573d073edf81270a015b38cc05cefAffected Packages
(1 across 1 ecosystem)
PyPI(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| openexr | 3.3.0 ... 3.4.4 (12 versions) | 3.4.5 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 28× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-18 19:50 UTCOSV refresh
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 19:27 UTCEPSS rescore
- 2026-09-17 19:30 UTCEPSS rescore
- 2026-09-16 14:08 UTCEPSS rescore
- 2026-09-16 05:15 UTCEPSS rescore
- 2026-09-13 16:47 UTCEPSS rescore
- 2026-09-12 15:01 UTCEPSS rescore
- 2026-09-11 14:52 UTCEPSS rescore
- 2026-09-10 09:34 UTCEPSS rescore
- 2026-09-08 22:00 UTCEPSS rescore
- 2026-09-07 16:01 UTCEPSS rescore
- 2026-09-06 13:47 UTCEPSS rescore
- 2026-09-06 13:47 UTCEPSS rescore
- 2026-09-04 05:06 UTCEPSS rescore
- 2026-09-02 14:11 UTCEPSS rescore
- 2026-09-01 13:53 UTCEPSS rescore
- 2026-09-01 04:39 UTCEPSS rescore
- 2026-08-30 22:47 UTCOSV refresh
- 2026-08-30 19:17 UTCEPSS rescore
- 2026-08-30 01:22 UTCEPSS rescore
- 2026-08-28 21:41 UTCEPSS rescore
- 2026-08-27 14:25 UTCEPSS rescore
- 2026-08-26 14:46 UTCEPSS rescore
- 2026-08-25 13:48 UTCEPSS rescore
Show 34 moreShow fewer
- 2026-08-23 00:19 UTCEPSS rescore
- 2026-08-21 23:49 UTCEPSS rescore
- 2026-08-20 22:55 UTCEPSS rescore
- 2026-08-19 17:03 UTCEPSS rescore
- 2026-08-18 13:48 UTCEPSS rescore
- 2026-08-17 13:47 UTCEPSS rescore
- 2026-08-16 14:56 UTCEPSS rescore
- 2026-08-16 02:14 UTCEPSS rescore
- 2026-08-15 01:30 UTCEPSS rescore
- 2026-08-14 09:09 UTCEG score recompute
- 2026-08-13 22:00 UTCEPSS rescore
- 2026-08-13 01:09 UTCEG score recompute
- 2026-08-12 13:50 UTCEPSS rescore
- 2026-08-11 13:42 UTCEPSS rescore
- 2026-08-11 07:11 UTCEG score recompute
- 2026-08-11 00:00 UTCEPSS rescore
- 2026-08-10 08:58 UTCEG score recompute
- 2026-08-09 13:46 UTCEPSS rescore
- 2026-08-09 08:46 UTCEG score recompute
- 2026-08-08 16:37 UTCEPSS rescore
- 2026-08-07 20:54 UTCEG score recompute
- 2026-08-06 13:46 UTCEPSS rescore
- 2026-08-06 03:09 UTCEG score recompute
- 2026-08-05 19:17 UTCEPSS rescore
- 2026-08-04 15:10 UTCEPSS rescore
- 2026-08-04 06:00 UTCEG score recompute
- 2026-08-03 10:36 UTCEPSS rescore
- 2026-08-02 19:43 UTCEG score recompute
- 2026-08-02 02:26 UTCEPSS rescore
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:27 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-28 15:36 UTCEPSS rescore
- 2026-07-27 13:34 UTCEG score recompute
Frequently asked(5)
What is CVE-2026-26981?
When was CVE-2026-26981 disclosed?
Is CVE-2026-26981 actively exploited?
What is the CVSS score of CVE-2026-26981?
How do I remediate CVE-2026-26981?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-26981
Is Your Infrastructure Affected by CVE-2026-26981?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.