LinkAce - Stored XSS via Unsanitized SSO User's Name Rendered in Admin Audit Log Allows Session Hijacking

published 2026-05-28 5 mo ago modified 2026-07-21 3 mo ago also EUVD-2026-33055

cvss: 8.5; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits: 0; none known

LinkAce is a self-hosted archive to collect website links. Prior to 2.5.6, LinkAce contains a stored cross-site scripting vulnerability that allows a low-privilege user to execute arbitrary JavaScript in an administrator's browser session. This affects instances configured with SSO/OAuth authentication, which is one of the supported authentication methods in LinkAce. An attacker who sets their OAuth display name to a malicious script and then creates an API token will plant a persistent XSS payload in the audit log. When any admin navigates to /system/audit, the payload executes in the admin's browser context. This enables session cookie theft, CSRF token exfiltration (exposed in the la-app-data meta tag), or any other action the admin can perform. This vulnerability is fixed in 2.5.6.

Patch / fix

fixed in 1

linkace linkace 2.5.6

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 5 mo ago (2026-05-30)

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/Kovah/LinkAce/security/advisories/GHSA-jx4g-ph82-x9mm referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	8.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

Kovah LinkAce

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

github.com /Kovah/LinkAce/security/advisories/GHSA-jx4g-ph82-x9mm
exploit

Sources

CVE List CVE-2026-45343
NVD CVE-2026-45343

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary