CVE-2026-75698

Executive Summary

CVE-2026-75698 is a reflected Cross-Site Scripting (XSS) vulnerability in Adobe Connect, exploitable when an authenticated or unauthenticated victim is induced to visit a maliciously crafted URL or interact with a compromised web page. The vulnerability carries a CVSS v3.1 base score of 9.3 (Critical), driven by network reachability, low attack complexity, no privileges required, and a scope change that allows the injected script to compromise resources beyond the vulnerable component. There is currently no patch, no public proof-of-concept, and no exploit code in circulation according to the tracked sources, but the combination of reflected input handling and a scope-changing impact profile makes this a high-priority item for any organization exposing Adobe Connect to untrusted networks.

Technical Analysis

The vulnerability class is CWE-79, Improper Neutralization of Input During Web Page Generation ("Cross-Site Scripting"), specifically the reflected subtype. In a reflected XSS defect, user-controllable input supplied through a request is echoed back into the generated HTML response without adequate output encoding or contextual escaping. The browser then parses that response and executes the injected markup or script in the origin of the vulnerable application, because the response is served from the trusted Adobe Connect domain.

Several properties of this CVE are notable from a threat-modeling standpoint:

1. Reflection rather than persistence. Because the payload is reflected, it is not stored server-side. The victim must be steered to a crafted link. This makes the vulnerability a delivery-dependent issue: the attacker's problem is social engineering and URL obfuscation, not persistence on the target server.
2. Scope is changed (S:C). The CVSS vector indicates the exploited component can affect resources beyond its own security scope. Practically, this means script executed in the context of Adobe Connect can reach data and actions outside the immediate vulnerable page — for example, cross-origin or cross-privilege operations that the vulnerable component is trusted to perform. This is why both Confidentiality and Integrity are rated High while Availability is None (A:N): the flaw manipulates data and session trust rather than causing denial of service.
3. User interaction required (UI:R), but no privileges (PR:N). An unauthenticated attacker can craft the payload; the victim supplies the interaction. Where the victim is already authenticated to Adobe Connect, the injected script inherits that session context.
4. No authentication needed to launch (PR:N) and network exploitable (AV:N). The attack can originate from the public internet, and complexity is Low (AC:L), meaning no specialized conditions must be satisfied for the payload to reflect and execute.

The NVD description does not disclose the specific request parameter, endpoint, route, or rendering template involved in the reflection. No CNA title was supplied, and no affected-version range was provided. Because of this, the precise injection sink and the exact encoding failure cannot be asserted. Any report claiming a specific parameter name, file path, or URL endpoint for this CVE would be inventing details. What can be stated with confidence, based on the vulnerability class and the CVSS vector, is that the flaw lies in how Adobe Connect constructs an HTML response from request-supplied input, and that the resulting injection executes in the application's origin with the victim's session privileges.

For defenders, the practical takeaway is that the vulnerable surface is any Adobe Connect endpoint that reflects request data into a rendered page. The attack does not require a malformed request body, an unusual content type, or an authentication bypass — only that the crafted URL be opened by a user.

Exploitation Scenarios

The following attack chain is described strictly at the vulnerability-class level. No public PoC, exploit code, or Nuclei template exists for CVE-2026-75698, and the NVD description does not name any endpoint, parameter, or function. Specific request shapes are therefore not asserted here; the sequence below reflects how reflected XSS in a web application of this type is typically operationalized.

1. Reconnaissance and target identification. The attacker identifies internet-facing or VPN-accessible Adobe Connect deployments. This is achievable through search-engine queries for Adobe Connect login and meeting pages, certificate transparency lookups, and Shodan-style asset discovery. The attacker does not need credentials to identify a target, consistent with PR:N.

2. Triggering the flaw class. The attacker constructs a URL in which a request parameter that the application reflects into its HTML output is populated with script-bearing markup. On delivery, the application returns a page containing that unescaped value. The victim's browser, parsing the response as HTML from the Adobe Connect origin, executes the script. This is the standard reflected-XSS mechanism: output encoding is missing or contextually incorrect for the sink in which the input lands. No attacker-controlled state is stored on the server, consistent with a reflected (non-persistent) defect.

3. Payload delivery and execution. Delivery is via a link — phishing email, chat message, calendar invite, social engineering, or a "compromised web page" as stated in the NVD description. The attacker's payload is JavaScript executing in the context of the Adobe Connect origin. Because UI:R is required, the victim must click or otherwise load the crafted URL. Because S:C applies, the executed script is not confined to the single page; it can act on resources the vulnerable component is trusted to reach.

4. Post-exploitation impact. Once the script executes, the attacker can perform actions as the victim's session: exfiltrate page content, session tokens, or account data reachable from the browser context; act on behalf of the victim within the application; redirect the victim; or capture credentials via injected content rendered in the trusted origin. Because Integrity and Confidentiality are both High, account or session takeover and data manipulation are realistic outcomes. The score reflects session and data compromise as the primary impact, not service disruption.

Because the vulnerability is reflected, the attacker gains nothing without a successful lure. Detection and user awareness therefore have outsized value relative to the technical severity alone.

Impact Assessment

With a CVSS v3.1 base score of 9.3, this is a Critical-severity finding. The individual contributions are:

• AV:N (Network). Exploitation can be launched over the internet against the application.
• AC:L (Low). No special conditions are required to weaponize or deliver the payload.
• PR:N (None). The attacker requires no account or privilege on the target.
• UI:R (Required). A user must visit the crafted URL or interact with a compromised page. This is the only gating factor and is routinely overcome through phishing.
• S:C (Changed). Impact extends beyond the vulnerable component to other resources — the reason the score escalates into the 9.x band rather than remaining in the 6–8 range typical of many stored-XSS findings.
• C:H / I:H. High confidentiality and integrity impact: session tokens, account data, and in-application state can be read and modified.
• A:N (None). No availability impact; this is not a DoS finding.

Affected systems. Adobe Connect deployments accessible to users via browser, including meeting, login, and content-serving interfaces. Conferencing and webinar platforms are high-value targets because users authenticate to them and administrators often operate privileged content-management functions from the same origin.

Blast radius. Two tiers. First, the individual user: session hijack, account takeover, and exposure of content the victim can access in Adobe Connect. Second, the deployment: because S:C permits impact outside the immediate component, an administrator induced to execute the reflected payload can expose administrative functionality, allowing content manipulation, user-account changes, or harvesting of meeting artifacts, recordings, or stored files. In regulated environments, exfiltration of meeting recordings or shared documents also creates a data-protection and compliance event.

Business impact. Session and account compromise of an internal user population, potential downstream abuse of legitimate Adobe Connect accounts for further phishing (a compromised conferencing account is an effective lure source), and reputational/regulatory consequences if sensitive meeting content is exposed. Given PR:N and AV:N, exposure is bounded only by who can reach the deployment.

Detection Guidance

Detection for reflected XSS is primarily payload- and parameter-oriented. Because the exact request surface for this CVE is undisclosed, the rules below are written to be generic-but-realistic detectors for script-bearing values in HTML-reflecting requests to an Adobe Connect deployment. Analysts should tune parameter whitelists to their environment and treat alerts as triage signals rather than definitive exploitation evidence.

Sigma Rule

title: Potential Reflected XSS Attempt Against Adobe Connect
id: 8f3a1c2e-5b7d-4a9f-9c21-7d6e0b4f2a10
status: experimental
description: Detects HTTP requests to Adobe Connect with script-bearing payloads in the query string, indicative of reflected XSS probing and exploitation.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-75698
author: Threat Intelligence
date: 2026/01/01
tags:
  - attack.t1059.007
  - attack.t1189
logsource:
  category: webserver
  product: webserver
detection:
  selection_host:
    cs-host|contains:
      - 'connect'
  selection_method:
    cs-method:
      - 'GET'
      - 'POST'
  selection_payload:
    cs-uri-query|contains:
      - '<script'
      - '%3Cscript'
      - 'javascript:'
      - 'onerror='
      - 'onload='
      - 'onmouseover='
      - 'svg/onload'
      - '%3Csvg'
      - 'document.cookie'
      - 'alert('
  condition: selection_method and selection_payload
fields:
  - c-ip
  - cs-uri-stem
  - cs-uri-query
  - cs-user-agent
falsepositives:
  - Legitimate application or scanner traffic that passes encoded HTML
  - Security tooling performing authorized assessments
level: medium

YARA Rule

rule CVE_2026_75698_Adobe_Connect_XSS_Reflection
{
    meta:
        description = "Detects reflected XSS payload patterns associated with CVE-2026-75698 in Adobe Connect HTTP traffic or logs"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-75698"
        author = "Threat Intelligence"
        date = "2026-01-01"
        severity = "high"

    strings:
        $script_tag   = "<script" nocase ascii wide
        $script_enc   = "%3Cscript" nocase ascii
        $js_proto     = "javascript:" nocase ascii wide
        $evt_onerror  = "onerror=" nocase ascii wide
        $evt_onload   = "onload=" nocase ascii wide
        $evt_onmouse  = "onmouseover=" nocase ascii wide
        $svg_onload   = "svg/onload" nocase ascii
        $cookie_theft = "document.cookie" nocase ascii wide
        $srcdoc       = "srcdoc=" nocase ascii
        $img_tag      = "<img" nocase ascii wide

    condition:
        filesize < 1MB and
        (
            any of ($script_tag, $script_enc, $js_proto, $svg_onload, $srcdoc)
            or (2 of ($evt_onerror, $evt_onload, $evt_onmouse, $cookie_theft))
            or ($img_tag and any of ($evt_onerror, $evt_onload))
        )
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-75698 Possible Reflected XSS Attempt Against Adobe Connect"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"<script"; nocase; http.uri; content:"%3Cscript"; nocase; http.uri; content:"onerror="; nocase; http.uri; content:"javascript:"; nocase; http.user_agent; content:"connect"; nocase; classtype:web-application-attack; reference:cve,2026-75698; reference:url,nvd.nist.gov/vuln/detail/CVE-2026-75698; sid:9000001; rev:1;)

Note: Suricata matches each content as an independent condition by default; the rule above is written for readability. In production, split these into separate rules or use pcre with an alternation so that a single payload token triggers the alert, and anchor with http.uri buffers to reduce false positives.

alert http any any -> any any (msg:"CVE-2026-75698 Adobe Connect XSS Payload In URI"; flow:established,to_server; http.method; content:"GET"; http.uri; pcre:"/(%3C|<)script|on(error|load|mouseover)\s*=|svg\/onload|javascript:/i"; classtype:web-application-attack; reference:cve,2026-75698; sid:9000002; rev:1;)

Elastic Detection

sequence by source.ip with maxspan=30s
  [ network where network.protocol == "http" and
      http.request.method in ("GET", "POST") and
      (http.request.uri.query : "*<script*" or
       http.request.uri.query : "*%3Cscript*" or
       http.request.uri.query : "*onerror=*" or
       http.request.uri.query : "*onload=*" or
       http.request.uri.query : "*javascript:*" or
       http.request.uri.query : "*svg/onload*" or
       http.request.uri.query : "*document.cookie*") and
      (http.request.headers.host : "*connect*" or
       url.domain : "*connect*") ]

Single-event variant where sequencing is not required:

network where network.protocol == "http" and
  http.request.method in ("GET", "POST") and
  http.request.uri.query regex ".*(%3C|<)script.*" and
  (http.request.headers.host : "*connect*" or url.domain : "*connect*")

Splunk SPL Query

index=web sourcetype=access_combined
| eval q=lower(coalesce(uri_query, cs_uri_query, ""))
| where match(q, "(<|%3c)script") OR match(q, "on(error|load|mouseover|click)\s*=") OR match(q, "javascript:") OR match(q, "svg/onload") OR match(q, "document\.cookie") OR match(q, "srcdoc=")
| stats count min(_time) as first_seen max(_time) as last_seen values(uri) as uris values(cs_uri_query) as queries by src_ip, host, user_agent
| where count >= 1
| convert ctime(first_seen) ctime(last_seen)
| sort -count

Wazuh OSSEC Rule

<group name="web,appsec,cve-2026-75698,">
  <rule id="100301" level="10">
    <if_sid>31100,31101,31108</if_sid>
    <field name="url">\.*(%3C|<)script|on(error|load|mouseover|click)\s*=|javascript:|svg/onload|document\.cookie|srcdoc=</field>
    <description>CVE-2026-75698: Possible reflected XSS payload against Adobe Connect (script-bearing request URI)</description>
    <mitre>
      <id>T1059.007</id>
      <id>T1189</id>
    </mitre>
    <group>attack,xss,</group>
  </rule>

  <rule id="100302" level="12">
    <if_sid>100301</if_sid>
    <field name="url">(document\.cookie|localStorage|sessionStorage|fetch\(|XMLHttpRequest)</field>
    <description>CVE-2026-75698: Reflected XSS payload with likely data-exfiltration primitives in URI</description>
    <group>attack,xss,exfiltration,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence is 0/4 — UNPATCHED. No vendor advisory reference, hotfix, patched build number, or fixed version range was identified in any tracked source for CVE-2026-75698. There is no confirmed vendor fix and no published workaround. Organizations should treat this as an open exposure until Adobe publishes a remediation, and should monitor Adobe's security bulletin channel directly. Because no affected-version data was supplied, assume all deployed versions are potentially impacted until version applicability is confirmed with the vendor or through testing.

1) Immediate mitigations (compensating controls while unpatched):

• Put Adobe Connect behind a web application firewall or reverse proxy with an XSS ruleset and enable request-inspection and output-encoding enforcement where the platform permits it.
• Restrict network accessibility of Adobe Connect to known user populations (VPN, IP allowlists, zero-trust application gateways) to reduce the reachable attacker pool, since the flaw is network-exploitable with no privileges.
• Enforce a strict Content-Security-Policy on the Adobe Connect origin if the deployment allows header injection at the reverse proxy — a policy that forbids unsafe-inline and restricts script-src to known-good hosts materially reduces reflected-XSS impact.
• Deploy URL filtering and email gateway rules that detect and quarantine links containing encoded script markers, and enable link rewriting with detonation on inbound mail.
• Increase user awareness for the specific lure: an unsolicited Adobe Connect meeting or login link that must be clicked. Given UI:R is the sole gating factor, reducing click-through is a direct mitigation.
• Harden session cookies (Secure, HttpOnly, SameSite=Strict where compatible) at the proxy layer to limit token theft if a payload executes. Note this reduces but does not eliminate impact, since scope is changed and the script runs in-origin.

2) Patch / upgrade steps (once a fix is available):

• Monitor Adobe's official security advisories and the Adobe Connect release notes for a bulletin referencing this identifier or the underlying reflected-XSS fix.
• When a fixed build is published, inventory all Adobe Connect instances — including on-premises, managed-hosting, and any federated or embedded deployments — and schedule emergency change windows consistent with the 9.3 severity.
• Validate the fix by re-testing the reflecting request surface in a staging environment before broad rollout; do not assume the presence of a version string alone confirms the sink is closed.
• If the deployment is Adobe-hosted (Adobe Connect managed services), track the vendor-side remediation status rather than an on-premises upgrade path.

3) Long-term hardening:

• Adopt context-aware output encoding as a standing requirement across custom Adobe Connect pods, integrations, and any first-party wrappers around the platform.
• Establish a routine for reviewing third-party components and embeddings that render user-supplied content within the Adobe Connect origin.
• Maintain continuous vulnerability scanning of internet-facing collaboration platforms and correlate findings with vendor advisories to close the gap between public disclosure and vendor patch.
• Include XSS-specific test cases (reflected parameter fuzzing, CSP bypass attempts) in periodic penetration tests of the conferencing stack.
• Retain web access logs long enough to investigate exploitation retrospectively, since reflected-XSS campaigns are often link-based and may not generate obvious server-side anomalies.

References

• NVD — CVE-2026-75698: https://nvd.nist.gov/vuln/detail/CVE-2026-75698
• CWE-79, Improper Neutralization of Input During Web Page Generation ("Cross-Site Scripting"): https://cwe.mitre.org/data/definitions/79.html
• Adobe Security Bulletins and Advisories (vendor channel for the eventual fix): https://helpx.adobe.com/security.html
• MITRE ATT&CK T1059.007 — Command and Scripting Interpreter: JavaScript: https://attack.mitre.org/techniques/T1059/007/
• MITRE ATT&CK T1189 — Drive-by Compromise: https://attack.mitre.org/techniques/T1189/

Exploit-in-the-wild and campaign status: No public proof-of-concept, exploit code, or Nuclei template was identified for CVE-2026-75698 in the tracked sources. The CVE is not listed in CISA's Known Exploited Vulnerabilities catalog. No threat actor attribution or active-campaign reporting is available. EPSS has not yet scored this CVE; no estimate of exploitation likelihood should be inferred until FIRST.org publishes a value. Given the 9.3 severity, the weaponizable nature of reflected XSS, and the absence of a patch, monitoring for weaponization is warranted even without current evidence of exploitation.