Should you update to Adobe Acrobat Reader 26.002.21901?
Yes, this week. Adobe Acrobat Reader 26.002.21901 is a security update Adobe released on 8 Sep 2026 for Mac and Windows. It fixes 32 security flaws, 21 rated critical and 11 important by Adobe.[1] None of them is known to be used in attacks.
It is the newest Adobe Acrobat Reader release, so it’s the one to have.
Should you update?
Yes, this week. Adobe rates 21 fixes critical, and attackers study each release to work out what it fixed. Every security update closes holes that become public the moment it ships, so the risk of staying on the old version only grows. Waiting a week to see if others hit problems is a common habit; with a security update it’s the wrong trade.
Is Adobe Acrobat Reader 26.002.21901 safe to install?
Yes. It’s Adobe’s own security release, and updates rarely go wrong; a backup makes it painless if one does. The one unsafe way to get it is from a link: Adobe never sends updates by email, text or pop-up, so install it only from Reader’s own Check for Updates.
What it fixes
Adobe lists 32 security flaws, 21 rated critical and 11 important by Adobe.[1] The 32 critical and important ones are:
| Flaw | Severity | What Adobe calls it |
|---|---|---|
CVE-2026-81996 | Critical | Incorrect Authorization |
CVE-2026-81994 | Critical | Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') |
CVE-2026-81983 | Critical | Out-of-bounds Write |
CVE-2026-79907 | Critical | Double Free |
CVE-2026-79908 | Critical | Out-of-bounds Write |
CVE-2026-79909 | Critical | Use After Free |
CVE-2026-80161 | Critical | Access of Resource Using Incompatible Type ('Type Confusion') |
CVE-2026-81973 | Critical | Use After Free |
CVE-2026-81975 | Critical | Use After Free |
CVE-2026-81976 | Critical | Use After Free |
CVE-2026-81992 | Critical | Heap-based Buffer Overflow |
CVE-2026-81979 | Critical | Out-of-bounds Write |
CVE-2026-81980 | Critical | Out-of-bounds Write |
CVE-2026-81981 | Critical | Out-of-bounds Write |
CVE-2026-81985 | Critical | Use After Free |
CVE-2026-81986 | Critical | Use After Free |
CVE-2026-81987 | Critical | Integer Overflow or Wraparound |
CVE-2026-81988 | Critical | Use After Free |
CVE-2026-81989 | Critical | Use After Free |
CVE-2026-81990 | Critical | Use After Free |
CVE-2026-80159 | Critical | Untrusted Search Path |
CVE-2026-81997 | Important | Incorrect Authorization |
CVE-2026-81982 | Important | Out-of-bounds Read |
CVE-2026-82001 | Important | Uncontrolled Resource Consumption |
CVE-2026-80160 | Important | Out-of-bounds Read |
CVE-2026-80162 | Important | Use After Free |
CVE-2026-81977 | Important | Integer Underflow (Wrap or Wraparound) |
CVE-2026-81978 | Important | Out-of-bounds Read |
CVE-2026-81993 | Important | Heap-based Buffer Overflow |
CVE-2026-81984 | Important | Use After Free |
| and 2 more | ||
How to update, and how long it takes
A few minutes. Reader restarts.
- Open Acrobat Reader.Choose Help → Check for Updates.
- Let it install.Close any PDFs it asks about; Reader restarts when it’s done.
To check it worked: Choose Help → About Adobe Acrobat Reader (on a Mac, Acrobat Reader → About): it shows the version. It should say 26.002.21901 or later.
26.001.21662 vs 26.002.21901
Adobe Acrobat Reader 26.001.21662, released 9 Jun 2026, fixed 21 security flaws. Adobe Acrobat Reader 26.002.21901 fixes 32 security flaws and includes the fixes before it, so going straight to 26.002.21901 gets you both.
- Before: Adobe Acrobat Reader 26.001.21662, 9 Jun 2026, 21 security flaws
- After: none yet. This is the newest.
- Adobe Acrobat Reader updates, every release and the latest version
- Updates, the latest version of everything HARD tracks
References
- ^ Adobe. “Adobe security bulletin APSB26-141”, 8 Sep 2026.