CVE-2026-34707

Code execution via heap buffer overflow

Published Jun 9, 2026 · Updated Jun 9, 2026

Heap-based buffer overflow in Adobe InCopy 21.3 and 20.5.3 and earlier allows context-dependent attackers to execute arbitrary code. Adobe has not disclosed the affected parser, file format, or the specific unchecked heap write that corrupts memory. Exploitation requires a victim to open a malicious file, and resulting code runs with the victim's user privileges.

CVSS severity7.8
High
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Heap-based buffer overflow in Adobe InCopy 21.3 and 20.5.3 and earlier allows context-dependent attackers to execute arbitrary code. Adobe has not disclosed the affected parser, file format, or the specific unchecked heap write that corrupts memory. Exploitation requires a victim to open a malicious file, and resulting code runs with the victim's user privileges.

The record

CVE
CVE-2026-34707
Published
Jun 9, 2026
Updated
Jun 9, 2026
Vendor
Adobe
Product
InCopy
Classifications
CWE-122, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=20.5.3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · InCopyversion=0 <=20.5.3

Published CVSS scores

7.8Adobe Systems IncorporatedCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow
T1204.002User Execution: Malicious File

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo