Security readout for executives and security teams
Plain-English summary
A flaw in UC Browser for Android can let a malicious link run attacker-controlled JavaScript as though it came from another website. Successful exploitation could expose sensitive page data or allow actions within a victim’s authenticated web session. The documented attack requires user interaction.
Executive priority
Treat this as an urgent endpoint-control issue. Identify affected Android devices immediately and prevent this browser version from accessing sensitive applications. Prioritize devices used by privileged personnel or for authenticated business services. Active exploitation is not established, but the potential session and data impact is severe.
Technical view
UC Browser package com.UCMobile.intl version 13.7.8.1314 contains universal cross-site scripting. A reflected XSS on a UC-owned domain can access an internal JavaScript bridge, register a deferred callback, navigate to another origin, and execute JavaScript there after a login dialog is dismissed. The origin boundary violation affects confidentiality and integrity.
Likely exposure
Confirmed exposure is limited by the supplied evidence to Android devices running package com.UCMobile.intl version 13.7.8.1314. Other versions are not established as affected or safe. Risk is greatest where the browser accesses authenticated business services or sensitive web data.
Exploitation context
The CVSS score is 9.3 with network reachability, low complexity, no required privileges, user interaction, and changed scope. The record is not in KEV, and the supplied sources do not establish active exploitation. Proof-of-concept references exist, but this assessment provides no reproduction or weaponization details.
Researcher notes
The key security failure is JavaScript execution surviving navigation across origins through an internal bridge callback. Assessment scope is constrained because the bundle names one package version, lists no CPEs, identifies no vendor fix, and provides no active-exploitation evidence. Testing should remain authorized and non-production.
Mitigation direction
- Inventory managed Android devices for package com.UCMobile.intl and version 13.7.8.1314.
- Remove or disable the affected browser where operationally feasible.
- Block installation or use through mobile-device management until vendor guidance confirms a safe version.
- Direct users to an approved alternative browser for authenticated or sensitive services.
- Check vendor guidance for an official update or mitigation; none is identified in the supplied evidence.
Validation and detection
- Verify installed package names and versions through device-management inventory.
- Confirm affected installations are removed, disabled, or prevented from accessing sensitive services.
- Review web and mobile security telemetry for suspicious UC Browser link launches and cross-origin activity.
- Confirm any replacement version is explicitly identified as fixed by authoritative vendor or CVE guidance.
- Recheck the CVE record and KEV status for exploitation or remediation updates.
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-2026-78997 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
- Critical
- CVSS
- 9.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A: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:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N2.85.8CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
9.3CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A: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://gist.github.com/OmriInbar-Novee/9fd65fe08c1b1cff6a19350e44425de2CVE reference, mitre
- https://gist.github.com/OmriInbar-Novee/ef7a92db148b2eb1ab0aa7b99a565c4cCVE reference, mitre
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.