Skip to main content

CVE-2026-115758sumatrapdfreader sumatrapdf vulnerability

Schedule itHigh8.2EPSS 0.14%, higher than 4% of scored CVEs

CVE-2026-115758 is a vulnerability in sumatrapdfreader sumatrapdf, rated high (8.2 on CVSS 4.0).

Why this priority: High severity, with no exploitation signal yet.

Published · Updated · NVD status: Deferred

What it is

The record does not classify the weakness yet; the description below says what the reporter found.

How it is reached

An attacker can exploit it over the network, without an account, and nobody has to click anything. Success also depends on conditions the attacker does not fully control.

What an attacker gains

A successful attack can change data or behaviour.

Is it being exploited?

There is no public report of exploitation yet. EPSS estimates a 0.14% chance of exploitation activity in the next 30 days, higher than 4% of scored CVEs.

What to do

  1. No fixed version is listed yet. Find every place sumatrapdfreader sumatrapdf runs, watch the references for a fix, and plan a replacement if it is no longer supported.
  2. While there is no fix, keep it off the internet or behind a VPN, allowlist or authenticating proxy.

Description from NVD

SumatraPDF is a multi-format reader for Windows. In version 3.6.1 and earlier, HttpGet() in src/base/Http_win.cpp unconditionally passes INTERNET_FLAG_IGNORE_CERT_CN_INVALID to WinINet, disabling hostname matching for HTTPS update metadata and crash-symbol requests while retaining certificate-chain validation. A network-positioned attacker with a Windows-trusted certificate for an attacker-controlled domain can impersonate the project's update host, inject promo text and a clickable URL before update metadata validation, and provide an attacker-controlled archive to ExtractSymbols(). Installer replacement is not directly possible because HttpGetToFile() validates TLS and MaybeStartUpdateDownload() restricts the download host. No fixed version is available as of this review.

What this means for your architecture.

A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.

Components it touches

  • sumatrapdfreader sumatrapdf. Start from where it runs and what it is connected to.

Trust boundaries in play

  • Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.

Questions to answer about your own systems

  • Where does sumatrapdfreader sumatrapdf run in your systems, and at which version?
  • Which of those instances can be reached from the internet or partner networks?
  • What can it reach once compromised: which data stores, secrets and services?

Sources

  • CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
  • Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
  • Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
  • Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.