CVE Intelligence
CISA KEV High CSRF exploit reference

CVE-2023-2533 — PaperCut NG/MF Cross-Site Request Forgery (CSRF) Vulnerability

A Cross-Site Request Forgery (CSRF) vulnerability has been identified in PaperCut NG/MF, which, under specific conditions, could potentially enable an attacker to alter security settings or execute arbitrary code. This could be exploited if the target is an admin with a current login session. Exploiting this would typically involve the possibility of deceiving an admin into clicking a specially crafted malicious link, potentially leading to unauthorized changes.

Published Jun 20, 2023 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Fluid Attacks

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

CISA KEV · Jul 28, 2025
How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • EPSS 28.6% (30-day exploitation probability)+15
  • Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Jul 28, 2025
EPSS FIRST
28.62%
ahead of 98% of scored CVEs · Oct 14, 2026
Affects
PaperCut
Papercut Mf and 2 more
CVSS base
8.8
High · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

CISA required action CISA

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

US federal deadline: Aug 18, 2025 — passed 423 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (PaperCut Papercut Mf, PaperCut Papercut Ng, PaperCut PaperCut NG/MF).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  5. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  6. EPSS ahead of 98% of scored CVEs: prioritize it in the patch queue.
  7. Search available logs for exploit probes matching the vulnerability class (csrf), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
PaperCut Papercut Mf < 20.1.8≥ 21.0.0 and < 21.2.12≥ 22.0.0 and < 22.1.1 Vulnerable NIST National Vulnerability Database
PaperCut Papercut Ng < 20.1.8≥ 21.0.0 and < 21.2.12≥ 22.0.0 and ≤ 22.1.1 Vulnerable NIST National Vulnerability Database
PaperCut PaperCut NG/MF ≥ 22.0.10 and < 2.1.1 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.8 CVSS 3.1 High 2.8 5.9 nvd@nist.gov via NIST National Vulnerability Database
8.4 CVSS 3.1 High 1.7 6.0 help@fluidattacks.com via NIST National Vulnerability Database
8.4 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.4 CVSS 3.1 High — — Fluid Attacks via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.8 (NVD (NIST)) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-352 · Cross-Site Request Forgery (CSRF)

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Jul 28, 2025
Federal deadline
Aug 18, 2025
passed 423 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 28.62%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Hunt retroactively in logs from before Jul 28, 2025 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · papercut/papercut ng/mf
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Affected products added · papercut/papercut mf, papercut/papercut ng
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 8.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • 2025
  • Added to CISA KEV catalog
    Jul 27, 2025 · CISA
  • 2023
  • CVE published
    Jun 20, 2023 · Fluid Attacks

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

7 on the record

Elsewhere on this site

PaperCut
every CVE for this vendor
2025-07
what else CISA listed that month
CSRF
same class
CWE-352
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-87739 PaperCut MF/NG: User permissions are not evaluated on report generation 21d
  • CVE-2026-82077 PaperCut NG/MF: Remote Code Execution via Scan2Fax 21d
  • CVE-2026-14780 PaperCut NG/MF: Remote Code Execution via Scripting Subsystem 21d
  • CVE-2026-82078 PaperCut NG/MF Unsafe Reflection Vulnerability KEV Aug 28, 2026
  • CVE-2026-81578 PaperCut NG/MF Missing Authentication for Critical Function Vulnerability KEV Aug 28, 2026
  • CVE-2026-8793 PaperCut NG/MF: Insufficient brute-force protection Aug 3, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2023-2533 is "PaperCut NG/MF Cross-Site Request Forgery (CSRF) Vulnerability", rated High. It affects Papercut Mf (PaperCut); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 8.8 describes technical severity. EPSS 28.62% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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