How severe is CVE-2026-82078?

CVE-2026-82078 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-82078 being actively exploited?

Yes. CVE-2026-82078 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-08-31, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-82078?

CVE-2026-82078 primarily affects Papercut Papercut Mf. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-82078?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

When was CVE-2026-82078 published?

CVE-2026-82078 was published on 2026-08-28 and last updated on 2026-09-14.

CVE-2026-82078

CVE-2026-82078 is a critical-severity vulnerability in Papercut Papercut Mf with a CVSS 3.x base score of 9.1. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-08-31). The underlying weakness is classified as CWE-470.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v4: 9.4
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-08-31)
Weakness: CWE-470
Affected product: Papercut Papercut Mf
Published: 2026-08-28
Last modified: 2026-09-14

Description

An unsafe dynamic class loading vulnerability exists in the database connection utilities of PaperCut MF and PaperCut NG. The application instantiates database driver classes based on configurable driver names without validating against an allowlist of approved drivers. If an attacker can manipulate system configuration parameters, this enables the execution of arbitrary Java bytecode residing on the application classpath under the security context of the PaperCut server process.

Frequently asked questions

What is CVE-2026-82078?: An unsafe dynamic class loading vulnerability exists in the database connection utilities of PaperCut MF and PaperCut NG. The application instantiates database driver classes based on configurable driver names without validating against an allowlist of approved drivers. If an attacker can manipulate system configuration parameters, this enables the execution of arbitrary Java bytecode residing on the application classpath under the security context of the PaperCut server process.
How severe is CVE-2026-82078?: CVE-2026-82078 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-82078 being actively exploited?: Yes. CVE-2026-82078 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-08-31, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-82078?: CVE-2026-82078 primarily affects Papercut Papercut Mf. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-82078?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
When was CVE-2026-82078 published?: CVE-2026-82078 was published on 2026-08-28 and last updated on 2026-09-14.

References

Affected products (2)

cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*
cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*

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