High Memory corruption

CVE-2025-12840 — Academy Software Foundation OpenEXR EXR File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability

Academy Software Foundation OpenEXR EXR File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Academy Software Foundation OpenEXR. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of EXR files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-27948.

Published Dec 23, 2025 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: zdi

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1
Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.19%

ahead of 8% of scored CVEs · Oct 14, 2026

Affects

Academy Software Foundation

OpenEXR and 1 more

CVSS base

7.8

High · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Academy Software Foundation OpenEXR, Openexr Openexr).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Exploitation requires user interaction: tighten email/web filtering and warn affected users.
Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Academy Software Foundation	OpenEXR	version 3.4.0	Vulnerable	CVE Program (cve.org) e CISA ADP
Openexr	Openexr	< 3.4.3	Vulnerable	NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Local

Attack complexity

Low

Privileges required

None

User interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
7.8	CVSS 3.0	High	1.8	5.9	zdi-disclosures@trendmicro.com via NIST National Vulnerability Database
7.8	CVSS 3.0	High	—	—	zdi via CVE Program (cve.org) e CISA ADP

CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H (score shown at the top: zdi-disclosures@trendmicro.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-122 · Heap-based Buffer Overflow

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.19%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

endpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

2026
Affected products added · academy software foundation/openexr
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 7.8
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
2025
CVE published
Dec 23, 2025 · zdi

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

www.zerodayinitiative.com/advisories/ZDI-25-991/
Third Party Advisory, x_research-advisory, NIST National Vulnerability Database

Elsewhere on this site

Academy Software Foundation
every CVE for this vendor

Memory corruption
same class

CWE-122
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-45696 OpenEXR HTJ2K decoder heap buffer over-read in ht_undo_impl() (DoS) Jun 18, 2026
High CVE-2026-44663 OpenEXR: Integer overflow in the HTJ2K decoder leads to heap-buffer-overflow Jun 18, 2026
Critical CVE-2026-42217 OpenEXR: Shift exponent overflow in `readVariableLengthInteger()` (`ImfIDManifest.cpp`) May 7, 2026
Critical CVE-2026-42216 OpenEXR: Out-of-bounds read in `IDManifest::init()` during prefix expansion May 7, 2026
High CVE-2026-41142 OpenEXR is Vulnerable to Integer overflow in ImageChannel::resize leads to heap OOB write via OpenEXRUtil public API May 7, 2026
High CVE-2026-40244 OpenEXR has integer overflow in DWA setupChannelData planarUncRle pointer arithmetic (missed variant of CVE-2026-34589) Apr 20, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2025-12840 is "Academy Software Foundation OpenEXR EXR File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability", rated High. It affects OpenEXR (Academy Software Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.19% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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