CVE-2026-21357: Adobe InDesign Desktop · Heap-based Buffer Overflow
Affects Adobe InDesign DesktopSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 17% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| AdobeInDesign Desktop | Affected
| Fixed in– |
AI-suggested
- Monitor Adobe's official channels for patches and apply updates promptly once available to remediate the vulnerability.
- Until patches are released, implement strict file handling policies that restrict opening InDesign files from untrusted or unknown sources.
- Employ endpoint protection solutions capable of detecting anomalous behavior associated with heap-based buffer overflows or exploitation attempts.
- Educate users about the risks of opening unsolicited or suspicious files, emphasizing caution with email attachments and downloads.
- Utilize application whitelisting and sandboxing techniques to limit the impact of potential exploitation.
- Conduct regular backups of critical data to enable recovery in case of compromise.
- Implement network segmentation to reduce lateral movement if a system is compromised.
- Consider disabling or restricting Adobe InDesign usage on systems where it is not essential.
- Monitor security logs and alerts for signs of exploitation attempts targeting Adobe InDesign.
- Collaborate with incident response teams to prepare for potential exploitation scenarios.
Description
InDesign Desktop versions 21.1, 20.5.1 and earlier are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.