What is CVE-2025-20281?

CVE-2025-20281 is Cisco ISE API Unauthenticated Remote Code Execution Vulnerability. The supplied enrichment data classifies it as Injection mapped to CWE-74 Injection.

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?

9 public PoC repositories reported; 4 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, database audit logs 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-2025-20281 using CVSS 10, EPSS 97%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. 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: Lurk (), Shadow Network (), Watchdog (), Mana Team (). 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 KEVcriticalInjectionpublic exploit

CVE-2025-20281

CVE-2025-20281 — Cisco ISE API Unauthenticated Remote Code Execution Vulnerability

Q: Is it in CISA KEV?

Yes. The supplied enrichment data lists CVE-2025-20281 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 vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to execute arbitrary code on the underlying operating system as root. The attacker does not require any valid credentials to exploit this vulnerability. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by submitting a crafted API request. A successful exploit could allow the attacker to obtain root privileges on an affected device.

Published Jun 25, 2025Updated Jun 17, 2026Sources: NVD, Cisco (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 Jul 28, 2025

EPSS

97%

ahead of 99.9% of scored CVEs

Affects

Cisco

9 products listed

CVSS base

critical

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 Cisco Identity Services Engine Software to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

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 Aug 18, 2025 — passed 392 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
Cisco	Cisco Identity Services Engine Software	3.3.0	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.3 Patch 2	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.3 Patch 1	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.3 Patch 3	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.4.0	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.3 Patch 4	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.4 Patch 1	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.3 Patch 5	Vulnerable
Cisco	Cisco Identity Services Engine Software	3.3 Patch 6	Vulnerable

Attack characteristics

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

Availability

High

Confidentiality

High

Integrity

High

Scope

Changed

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
10	CVSS 3.1	critical	3.9	6	Cisco (CNA)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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-74 · Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Read Application Data
Bypass Protection Mechanism
Alter Execution Logic
Other

Mitigation: Programming languages and supporting technologies might be chosen which are not subject to these issues.

Weakness & attack patterns

CWE-74Injection

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

CAPEC-267 · Leverage Alternate EncodingCAPEC-71 · Using Unicode Encoding to Bypass Validation LogicCAPEC-46 · Overflow Variables and TagsCAPEC-83 · XPath InjectionCAPEC-3 · Using Leading 'Ghost' Character Sequences to Bypass Input FiltersCAPEC-273 · HTTP Response SmugglingCAPEC-13 · Subverting Environment Variable ValuesCAPEC-8 · Buffer Overflow in an API CallCAPEC-250 · XML InjectionCAPEC-47 · Buffer Overflow via Parameter ExpansionCAPEC-52 · Embedding NULL BytesCAPEC-42 · MIME Conversion

T1562.003Impair Defenses: Impair Command History Logging
T1574.006Hijack Execution Flow: Dynamic Linker Hijacking
T1574.007Hijack Execution Flow: Path Interception by PATH Environment Variable

CISA KEV details

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

CISAThat month →

Listed

Jul 28, 2025

Federal deadline

Aug 18, 2025

passed 392 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

4 of the 5 sampled are weaponized

Exploit entries

Exploit-DB and CTI exploit indexes

Malware

Families a CTI source ties to this CVE. One named, with the total it tracks.

Families tracked

Named

mirai

Mirai, win.mirai, mirai

Social mentions

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

2 more posts on this CVEShowing 5 of 7 · 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 Cisco Identity Services Engine Software.
Monitor for scanner or exploit-pattern traffic after 9 public PoC repositories were reported.

web/proxy/WAF logsapplication logsnetwork IDS/IPSdatabase audit logs

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.

LurkShadow NetworkWatchdogMana Team

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 10.0 (AV:N)
Jun 17, 2026 · NVD
2025
Added to CISA KEV catalog
Jul 28, 2025 · CISA
Initial · CVE published
Jun 25, 2025 · NVD

Source activity

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

13×SVRS was changedAug 29, 2025 – Mar 11, 2026 · SOCRadar CTI
8×TweetsSep 2, 2025 – Mar 11, 2026 · SOCRadar CTI
4×TelegramOct 8, 2025 – Jan 27, 2026 · SOCRadar CTI
4×CVE modified by MITRE: CVSS metrics updated.Oct 21, 2025 – Oct 28, 2025 · SOCRadar CTI

References

4 on the record

sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-unauth-rce-ZAd2GnJ6
Vendor Advisory, NIST, Mitre
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-20281
US Government Resource
www.zerodayinitiative.com/blog/2025/7/24/cve-2025-20281-cisco-ise-api-unauthenticated-remote-code-execution-vulnerability
Exploit, Third Party Advisory, NIST
nvd.nist.gov/vuln/detail/CVE-2025-20281
Vendor Advisory

Coverage

9 stories from the feeds we poll

4 more reports on this CVEShowing 5 of 9 · Vendor research and security press coverageUnlock free

Elsewhere on this site

Ciscoevery CVE for this vendor
July 2025what else CISA listed
Injectionsame class
CWE-74other 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.

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 record1

What should defenders know first?

CVE-2025-20281 is Cisco ISE API Unauthenticated Remote Code Execution Vulnerability, a critical vulnerability affecting Cisco Identity Services Engine Software from Cisco. The current evidence lists it in CISA KEV, and the exploit status is: Yes: CISA KEV signal present. Public exploit evidence is: 9 public PoC repositories reported; 4 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 10 describes technical severity, while EPSS 97% 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.