Critical Adobe Acrobat Flaw Lets Malicious PDFs Trigger One-Click Memory Corruption

What happened?

Adobe has fixed a flaw in Acrobat and Acrobat Reader that lets a malicious PDF corrupt memory when a user opens it. Tracked as CVE-2026-81983, the out-of-bounds write carries a CVSS score of 7.8 and could lead to code execution with the victim’s user rights. Adobe says it has seen no active exploitation so far. The bug sits in Acrobat’s image pipeline, code that starts parsing image data as soon as a PDF opens. Researchers found it with a custom Python fuzzer built largely with help from a large language model.

Key details

• Acrobat flaw lets PDF corrupt memory on open.
• Bug resides in Acrobat’s image pipeline.
• Root cause is 32‑bit integer overflow in Acrobat.dll.
• No active exploitation observed.

Summarised by SecOraLens from Cyber Security News. Always read the original source before acting. How SecOraLens verifies advisories.