What is CVE-2026-57909?

CVE-2026-57909 is WatchGuard Agent path traversal allows unauthenticated remote code execution. The supplied enrichment data classifies it as Auth Bypass mapped to CWE-306 Missing Authentication for Critical Function; CWE-94 Code 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?

Active exploitation is not confirmed from current sources for CVE-2026-57909. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

No. CVE-2026-57909 is not listed in CISA KEV in the supplied enrichment data. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Is there a public exploit?

A public PoC is not confirmed from current sources for CVE-2026-57909. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with identity provider logs, authentication 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-2026-57909 using CVSS 9.4, EPSS 0%, 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?

No public threat actor linkage is confirmed from current sources. 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. Prioritize based on EPSS, PoC availability, and external exposure. 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.

criticalAuth Bypass

CVE-2026-57909

CVE-2026-57909 — WatchGuard Agent path traversal allows unauthenticated remote code execution

A path traversal vulnerability in WatchGuard Agent allows a remote, unauthenticated attacker on an adjacent network to execute arbitrary code on an affected system.

Published Aug 25, 2026Updated Aug 25, 2026Sources: NVD, WatchGuard (CNA), GitHub, GitHub Security Advisory, SOCRadar CTI

Triage

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

Exploitation

Unreported

no source claims exploitation

EPSS

ahead of 0% of scored CVEs

Affects

WatchGuard

WatchGuard Agent

CVSS base

9.4

critical

Remediation

The vendor's own words where we have them.

WatchGuard Agent 1.25.13.0000

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.
Prioritize based on EPSS, PoC availability, and external exposure.
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
WatchGuard	WatchGuard Agent	0 to < 1.25.13.0000	Vulnerable

Attack characteristics

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

Scope

Attack Complexity

Low

Attack Vector

Adjacent

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
9.4	CVSS 4.0	critical	—	—	WatchGuard (CNA)

CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA: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-94 · Improper Control of Generation of Code ('Code Injection')

Bypass Protection Mechanism
Gain Privileges or Assume Identity
Execute Unauthorized Code or Commands
Hide Activities

Mitigation: Refactor your program so that you do not have to dynamically generate code.

CWE-306 · Missing Authentication for Critical Function

Gain Privileges or Assume Identity
Other

Mitigation: Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability. Identify all potential communication channels, or other means of interaction with the software, to ensure that all channels are appropriately protected. Developers sometimes perform authentication at the primary channel, but open up a secondary channel that is assumed to be private. For example, a login mechanism may be listening on one network port, but after successful authentication, it may open up a second port where it waits for the connection, but avoids authentication because it assumes that only the authenticated party will connect to the port. In general, if the software or protocol allows a single session or user state to persist across multiple connections or channels, authentication and appropriate credential management need to be used throughout.

Weakness & attack patterns

CWE-306Missing Authentication for Critical Function
CWE-94Code Injection

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

CAPEC-77 · Manipulating User-Controlled VariablesCAPEC-242 · Code InjectionCAPEC-35 · Leverage Executable Code in Non-Executable Files

T1027.006Obfuscated Files or Information: HTML Smuggling
T1027.009Obfuscated Files or Information: Embedded Payloads
T1564.009Hide Artifacts: Resource Forking

Detection

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

identity provider logsauthentication audit logs

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 9.4 (AV:A)
Aug 25, 2026 · NVD
Initial · CVE published
Aug 25, 2026 · NVD
Reported · CVE published
Aug 25, 2026 · WatchGuard
Added · GHSA-6fjc-c8m9-93pm published (critical)
Aug 25, 2026 · GitHub Security Advisory

Source activity

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

1×CVE modified by NIST, Cweid, Modified, LinkAug 25, 2026 · SOCRadar CTI

References

3 on the record

psirt.watchguard.com/CVE-2026-57909
Vendor Advisory
nvd.nist.gov/vuln/detail/CVE-2026-57909
NVD
github.com/advisories/GHSA-6fjc-c8m9-93pm
Exploit, Third Party Advisory

Elsewhere on this site

WatchGuardevery CVE for this vendor
Auth Bypasssame class
CWE-306other 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-2026-57909 is WatchGuard Agent path traversal allows unauthenticated remote code execution, a critical vulnerability affecting WatchGuard Agent from WatchGuard. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-57909. Public exploit evidence is: A public PoC is not confirmed from current sources for CVE-2026-57909. 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 9.4 describes technical severity, while EPSS 0% 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.