Security readout for executives and security teams
Plain-English summary
SillyTavern before 1.18.0 can echo attacker-controlled text into an error page without HTML escaping. That can create reflected cross-site scripting in the CORS proxy middleware. Business risk is highest where a SillyTavern instance is reachable by untrusted users or exposed beyond a trusted local environment.
Executive priority
Treat as a prompt maintenance issue unless SillyTavern is exposed outside a trusted local environment. Internet-facing or shared instances should be upgraded quickly because exploitation requires no authentication according to the CVSS vector.
Technical view
The vulnerable path is the CORS proxy middleware error handler. If fetch(url) throws, the response concatenates req.params.url and the error into res.status(500).send(...). Because the URL is attacker-controlled and unescaped, this is CWE-79 reflected XSS. The issue is fixed in SillyTavern 1.18.0.
Likely exposure
Affected exposure is SillyTavern versions earlier than 1.18.0. Sources do not provide CPEs or default deployment exposure details. Prioritize instances exposed to shared networks, remote users, reverse proxies, or the public internet.
Exploitation context
The CVE is not listed in KEV, and the supplied sources do not report active exploitation. CVSS 4.0 is 6.9 with network attack vector, low complexity, no privileges, and no user interaction indicated.
Researcher notes
The public evidence identifies the vulnerable code pattern, affected range, CWE, CVSS vector, and fixed version. It does not include CPEs, observed exploitation, or broader product impact. Avoid assuming exposure beyond SillyTavern before 1.18.0.
Mitigation direction
- Upgrade SillyTavern to version 1.18.0 or later.
- Identify and retire any SillyTavern instances below 1.18.0.
- Restrict access to trusted users and networks where upgrade is pending.
- Review the GitHub advisory for any updated vendor guidance.
Validation and detection
- Inventory deployed SillyTavern versions and confirm none are below 1.18.0.
- Check whether any instance is reachable by untrusted users or networks.
- Confirm proxy error responses no longer render raw URL input.
- Record compensating access controls for any delayed upgrade.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-44651 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.9 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N——GitHub_MVulnerability scoring details
Base CVSS 4.0 score
6.9MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/SillyTavern/SillyTavern/security/advisories/GHSA-xc4x-2452-5gc9CVE reference, GitHub_M · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.