sharpemu: Missing Authentication for Critical Functionality
CVE-2026-92704 is a high-severity missing authentication for critical functionality vulnerability in sharpemu, with a CVSS 3.1 base score of 8.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected sharpemu versions: < 0.0.3-release.3-patch.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of sharpemu you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
SharpEmu is an experimental PlayStation 5 emulator for Windows and Linux. In version 0.0.3-release.3 and earlier, the repository-provided debugger frontend tooling is vulnerable while running. This tooling is not included in the release archives. The frontend exposes an HTTP API on 127.0.0.1:8765 without authentication or CSRF token. Its do_POST handler in tools/SharpEmu.DebuggerFrontend/debugger_frontend.py does not validate the Origin, Referer, Sec-Fetch-Site, or Host headers. The _read_json_body() function also accepts JSON sent with browser-simple content types instead of requiring application/json . A malicious page that can reach the loopback listener can send cross-origin requests to /api/launch , /api/command , and /api/connect . Chromium may require Local Network Access permission for pages served from public origins. Local-origin pages and other delivery paths are not consistently subject to this restriction. The /api/launch endpoint accepts an attacker-selected emulatorPath if it points to an existing file on the victim’s host. On POSIX systems, that file must also be executable. The endpoint additionally requires an existing ebootPath . The /api/command endpoint exposes debugger operations, including write-memory , set-register , and continue . The /api/connect endpoint can initiate outbound TCP connections. These operations can let an attacker execute an existing binary with the victim’s privileges, control the attached emulated process, or reach network services accessible from the host. DNS rebinding can additionally let the attacker read API responses interactively. This issue is fixed in version 0.0.3-release.3-patch.1
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Authentication for Critical Functionality
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
- When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.
More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Missing Authentication for Critical Functionality vulnerabilities
- 8.5 High severity
- 8.4 High severity
- 8.1 High severity
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
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