CVE-2026-26981 | OpenEXR has heap-buffer-overflow via signed integer underflow in ImfContextInit.cpp

Exp

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.

Published: 2026-02-24 Last update: 2026-02-25 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-26981 is rated Exploit Available (55.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.52%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-26981

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-26981

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.52% +0.48%
2 2026-02-24 — 0.04% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-26981

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2026-26981

GitHub Security Advisory for CVE-2026-26981

GHSA-q6vj-wxvf-5m8c · Severity: medium · Ecosystem: pip — OpenEXR has heap-buffer-overflow via signed integer underflow in ImfContextInit.cpp

OS Trackers for CVE-2026-26981

vendor priority summary link
alpine — CVE-2026-26981: 1 source package rows (openexr); 4 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 4. https://security.alpinelinux.org/vuln/CVE-2026-26981
debian unimportant CVE-2026-26981 unimportant priority: Debian including 1 source packages (openexr), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-26981
redhat medium — https://access.redhat.com/security/cve/CVE-2026-26981
suse high CVE-2026-26981 severity important: SUSE including 36 source package names (libIex-3_2-31, libIex-3_2-31-x86-64-v3, …), 107 product×package rows across 22 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (22 product lines)): Known Not Affected 89, Fixed 18. https://www.suse.com/security/cve/CVE-2026-26981/
ubuntu medium CVE-2026-26981 medium priority: Ubuntu including 1 source packages (openexr), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, upstream, xenial): needs-triage 7. https://ubuntu.com/security/CVE-2026-26981

Affected software / configurations for CVE-2026-26981

Vendor Product Version Raw CPE
openexr openexr >= 3.3.0, < 3.3.7 cpe:2.3:a:openexr:openexr:*:*:*:*:*:*:*:*
openexr openexr >= 3.4.0, < 3.4.5 cpe:2.3:a:openexr:openexr:*:*:*:*:*:*:*:*

References for CVE-2026-26981

cvelogic Threat Intelligence