How severe is CVE-2021-27807?

CVE-2021-27807 has a CVSS score of 5.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2021-27807?

CVE-2021-27807 affects the following packages: org.apache.pdfbox:pdfbox (Maven). Ecosystems affected: Maven.

How do I fix CVE-2021-27807?

Update org.apache.pdfbox:pdfbox to 2.0.23 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-27807 is resolved across your whole dependency graph.

How do I detect CVE-2021-27807 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.pdfbox:pdfbox, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-27807 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2021-27807 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-27807 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-27807?

CVE-2021-27807 has an EPSS (Exploit Prediction Scoring System) score of 3.0%, placing it in the 87th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-27807?

CVE-2021-27807 is classified as CWE-834 (CWE-834). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-27807 published, and has it been updated?

CVE-2021-27807 was published on March 19, 2021 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

MEDIUM severity

CVE-2021-27807 — pdfbox

MEDIUMFix: apache/pdfbox@5c5a837

CVE-2021-27807 is a medium-severity (CVSS 5.5) CWE-834 vulnerability in org.apache.pdfbox:pdfbox. A fix is available for org.apache.pdfbox:pdfbox — see the affected versions and patch details below.

Excessive Iteration Denial of Service in Apache PDFBox

Also known asGHSA-2h3j-m7gr-25xj

Published

Mar 19, 2021

Updated

Oct 24, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

3.0%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs87th percentile — riskier than 87% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

☕org.apache.pdfbox:pdfbox

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

A carefully crafted PDF file can trigger an infinite loop while loading the file. This issue affects Apache PDFBox version 2.0.22 and prior 2.0.x versions.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.pdfbox:pdfbox`	≥ 2.0.0&&< 2.0.23	2.0.23`org.apache.pdfbox:pdfbox:2.0.23`

Affected Products

15 products · 31 configurations

Application

pdfboxapache

≥ 2.0.0 && ≤ 2.0.22

range

fedorafedoraproject

3 versions

323334

Application

banking trade finance process managementoracle

3 versions

14.2.014.3.014.5.0

Application

banking treasury managementoracle

1 version

14.5

Application

banking virtual account managementoracle

3 versions

14.2.014.3.014.5.0

communications messaging serveroracle

1 version

8.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.pdfbox:pdfbox, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.pdfbox:pdfbox to 2.0.23 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-27807 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Product	Fixed in	Advisory
Red Hat Fuse 7.9	`pdfbox`	RHSA-2021:3140
Red Hat Integration	see advisory	RHSA-2021:3205

Frequently Asked Questions

A carefully crafted PDF file can trigger an infinite loop while loading the file. This issue affects Apache PDFBox version 2.0.22 and prior 2.0.x versions.

O3 Security · Impact-Aware SCA

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CVE-2021-27807 — pdfbox

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2021-27807 in your dependencies?