What is CVE-2025-59718?

CVE-2025-59718 is Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability. The supplied enrichment data classifies it as Unclassified mapped to CWE-347 CWE-347.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Yes: CISA KEV signal present. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

Is there a public exploit?

6 public PoC repositories reported; 0 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with web/proxy/WAF logs, application logs, network IDS/IPS where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2025-59718 using CVSS 9.8, EPSS 69%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

Workarounds are not confirmed from current sources. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

Publicly linked actor or ransomware signals in the supplied enrichment data: Volt Typhoon (), Dark Partners (), Shadow Network (), APT 5 (), Cyber Alliance (). Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Treat as emergency remediation because CISA KEV status is present. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

CISA KEVcriticalpublic exploit

CVE-2025-59718

CVE-2025-59718 — Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability

Q: Is it in CISA KEV?

Yes. The supplied enrichment data lists CVE-2025-59718 in CISA KEV with required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

A improper verification of cryptographic signature vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2.0 through 7.2.11, FortiOS 7.0.0 through 7.0.17, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4.0 through 7.4.10, FortiProxy 7.2.0 through 7.2.14, FortiProxy 7.0.0 through 7.0.21, FortiSwitchManager 7.2.0 through 7.2.6, FortiSwitchManager 7.0.0 through 7.0.5 allows an unauthenticated attacker to bypass the FortiCloud SSO login authentication via a crafted SAML response message.

Published Dec 9, 2025Updated Jun 17, 2026Sources: NVD, Fortinet (CNA), CISA, FIRST EPSS, SOCRadar CTI

Triage

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

Exploitation

Confirmed

CISA KEV, listed Dec 16, 2025

EPSS

69%

ahead of 99.3% of scored CVEs

Affects

Fortinet

10 products listed

CVSS base

9.8

critical · 2 sources

CISA SSVC assessment

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

CISA

Exploitation

Active

none · proof-of-concept · active

Automatable

Yes

can an attacker script all four kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

Upgrade to FortiSwitchManager version 7.2.7 or above Upgrade to FortiSwitchManager version 7.0.6 or above Upgrade to FortiProxy version 7.6.4 or above Upgrade to FortiProxy version 7.4.11 or above Upgrade to FortiProxy version 7.2.15 or above Upgrade to FortiProxy version 7.0.22 or above Upgrade to FortiOS version 7.6.4 or above Upgrade to FortiOS version 7.4.9 or above Upgrade to FortiOS version 7.2.12 or above Upgrade to FortiOS version 7.0.18 or above Upgrade to FortiWeb version 8.0.1 or above Upgrade to FortiWeb version 7.6.5 or above Upgrade to FortiWeb version 7.4.10 or above Fortinet r…

CISA required action

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

Federal deadline Dec 23, 2025 — passed 269 days ago

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Treat as emergency remediation because CISA KEV status is present.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
Fortinet	FortiSwitchManager	7.2.0 to <= 7.2.6	Vulnerable
Fortinet	FortiSwitchManager	7.0.0 to <= 7.0.5	Vulnerable
Fortinet	FortiOS	7.6.0 to <= 7.6.3	Vulnerable
Fortinet	FortiOS	7.4.0 to <= 7.4.8	Vulnerable
Fortinet	FortiOS	7.2.0 to <= 7.2.11	Vulnerable
Fortinet	FortiOS	7.0.0 to <= 7.0.17	Vulnerable
Fortinet	FortiProxy	7.6.0 to <= 7.6.3	Vulnerable
Fortinet	FortiProxy	7.4.0 to <= 7.4.10	Vulnerable
Fortinet	FortiProxy	7.2.0 to <= 7.2.14	Vulnerable
Fortinet	FortiProxy	7.0.0 to <= 7.0.21	Vulnerable

Attack characteristics

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

Availability

High

Confidentiality

High

Integrity

High

Scope

Unchanged

Attack Complexity

Low

Attack Vector

Network

Privileges Req

None

User Interaction

None

Every base score collected

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

Score	Version	Severity	Expl.	Impact	Source
9.8	CVSS 3.1	critical	3.9	5.9	Fortinet (CNA)
9.1	CVSS 3.1	critical	—	—	Fortinet (CNA)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-347 · Improper Verification of Cryptographic Signature

Gain Privileges or Assume Identity
Modify Application Data
Execute Unauthorized Code or Commands

Weakness & attack patterns

CWE-347

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-463 · Padding Oracle Crypto AttackCAPEC-475 · Signature Spoofing by Improper Validation

CISA KEV details

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

CISAThat month →

Listed

Dec 16, 2025

Federal deadline

Dec 23, 2025

passed 269 days 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 date to argue against.

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

Exploit entries

Exploit-DB and CTI exploit indexes

Social mentions

Posts naming this CVE. Attention, not evidence of exploitation — it spikes on disclosure and decays whether or not anything is exploited.

35 more posts on this CVEShowing 5 of 40 · Who is discussing this CVE, and how loudlyUnlock free

Detection

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

Prioritize edge telemetry for network-reachable FortiSwitchManager, FortiOS, FortiProxy.
Monitor for scanner or exploit-pattern traffic after 6 public PoC repositories were reported.

web/proxy/WAF logsapplication logsnetwork IDS/IPS

Groups associated with this CVE

Groups reported in connection with this vulnerability. A reported association, not a confirmed observation of that group using it — and not scoped to any sector or campaign.

Volt TyphoonDark PartnersShadow NetworkAPT 5Cyber Alliance

11 more threat groups on this CVEShowing 5 of 16 · Attribution, campaigns and the malware each one runsUnlock free

ip38.60.212.9737
TweetFeed General · Nov 13, 2025
ip38.54.95.22638
Public Proxy Feed · Jul 7, 2024
ip38.54.88.20371
TweetFeed General · Nov 12, 2025
hostnamendibstersoft.com77
Kaspersky Public Requests · Feb 19, 2026
hostnameneremedysoft.com88
Maltrail Malware Feeds · Mar 10, 2026

5 more indicators on this CVEShowing 5 of 10 · Hashes, addresses and domains from a live threat exchangeUnlock free

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added · CVSS 3.1 9.8 (AV:N)
Jun 17, 2026 · NVD
2025
Added to CISA KEV catalog
Dec 16, 2025 · CISA
Initial · CVE published
Dec 9, 2025 · NVD

Source activity

Readings a source repeats on a schedule, counted rather than listed.

18×SVRS was changedFeb 23, 2026 – Jun 16, 2026 · SOCRadar CTI
12×TweetsMar 11, 2026 – Aug 19, 2026 · SOCRadar CTI
2×CVE modified by MITRE: CVSS metrics updated.Mar 20, 2026 – Jun 9, 2026 · SOCRadar CTI

References

6 on the record

fortiguard.fortinet.com/psirt/FG-IR-25-647
Vendor Advisory, Mitre, NIST
arcticwolf.com/resources/blog/arctic-wolf-observes-malicious-sso-logins-following-disclosure-cve-2025-59718-cve-2025-59719/
Third Party Advisory, NIST
cert-portal.siemens.com/productcert/html/ssa-864900.html
Third Party Advisory, NIST
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-59718
US Government Resource, NIST
docs.fortinet.com/upgrade-tool/fortigate
Vendor Advisory
nvd.nist.gov/vuln/detail/CVE-2025-59718
Vendor Advisory

Coverage

17 stories from the feeds we poll

12 more reports on this CVEShowing 5 of 17 · Vendor research and security press coverageUnlock free

Elsewhere on this site

Fortinetevery CVE for this vendor
December 2025what else CISA listed
Unclassifiedsame class
CWE-347other pages naming this weakness

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.

Only the 5 indicator(s) reported for this CVE are available; no packet-level or host-forensic 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 record1

What should defenders know first?

CVE-2025-59718 is Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability, a critical vulnerability affecting FortiSwitchManager, FortiOS, FortiProxy from Fortinet. The current evidence lists it in CISA KEV, and the exploit status is: Yes: CISA KEV signal present. Public exploit evidence is: 6 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 9.8 describes technical severity, while EPSS 69% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.