CVE-2026-34621: Adobe Acrobat and Reader Prototype Pollution Vulnerability

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HIGH 8.6EXPLOITEDUPGRADEUPGRADEUPGRADE

CVE-2026-34621 is a high-severity flaw (CVSS 8.6) affecting acrobat dc, acrobat reader dc, acrobat, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Acrobat Reader versions 24.001.30356, 26.001.21367 and earlier are affected by an Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') 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.

Why this priority

High severity
EPSS top 6%: very likely to be exploited
Exploited in the wild (CISA KEV)

A fixed release or distro patch exists.

Risk facts

CVSS score	8.6 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	7.2% (top 6%)
CISA exploited list	Yes, fix due 2026-04-27
Weakness	CWE-1321
Published	2026-04-11
Last modified	2026-10-26

Publisher (CNA): Adobe Systems Incorporated · Vendor: adobe

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-11 07:16 UTCPublished CVE record published
2026-04-13Exploited Added to the CISA Known Exploited Vulnerabilities list
2026-04-27Deadline CISA due date for US federal agencies to patch
2026-10-26 21:10 UTCUpdated Record last modified

adobe acrobat dc UPGRADE

Affected: < 26.001.21411

Fixed in: 26.001.21411

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy acrobat-dc || rpm -q acrobat-dc || acrobat-dc --version

2. UPGRADE to 26.001.21411 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade acrobat-dc

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade acrobat-dc

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

adobe acrobat reader dc UPGRADE

Affected: < 26.001.21411

Fixed in: 26.001.21411

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy acrobat-reader-dc || rpm -q acrobat-reader-dc || acrobat-reader-dc --version

2. UPGRADE to 26.001.21411 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade acrobat-reader-dc

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade acrobat-reader-dc

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

adobe acrobat UPGRADE

Affected: >= 24.0.0 and < 24.001.30362 · >= 24.0.0 and < 24.001.30360

Fixed in: 24.001.30360, 24.001.30362

Safe to downgrade to: a release before 24.0.0

1. Check installed version

apt-cache policy acrobat || rpm -q acrobat || acrobat --version

2. UPGRADE to 24.001.30360 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade acrobat

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade acrobat

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 24.0.0 (Debian / Ubuntu)

apt-cache madison acrobat sudo apt install acrobat=<VERSION_BEFORE_24.0.0> sudo apt-mark hold acrobat

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list acrobat sudo dnf downgrade acrobat-<VERSION_BEFORE_24.0.0> sudo dnf versionlock add acrobat

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

GitHub PoC: azefzafyoussef/CVE-2026-34621 (26 stars)
GitHub PoC: NULL200OK/cve_2026_34621_advanced (13 stars)
GitHub PoC: ercihan/CVE-2026-34621 (2 stars)

Verify at the official source NVD · CVE Program · CISA KEV catalog · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-34621?

acrobat dc: upgrade to 26.001.21411; acrobat reader dc: upgrade to 26.001.21411; acrobat: upgrade to 24.001.30360, 24.001.30362. Exact commands for each OS are on this page.

Is CVE-2026-34621 being exploited?

Yes. CVE-2026-34621 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.

What does CVE-2026-34621 affect?

CVE-2026-34621 affects acrobat dc, acrobat reader dc, acrobat. Severity is high (CVSS 8.6). Acrobat Reader versions 24.001.30356, 26.001.21367 and earlier are affected by an Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') vulnerability that could result in arbitrary code execution in the c

How urgent is CVE-2026-34621?

Priority 79/100. High severity; EPSS top 6%: very likely to be exploited; Exploited in the wild (CISA KEV)

Software pages

Adobe Acrobat vulnerabilities

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References

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