---
title: "Security digest: August 25, 2026"
url: https://erroneo.us/security/2026-08-25/
description: "August 25, 2026 vulnerability digest: 2 briefs (Next.js: Windows, AVIF and next/og RCEs (Aug-Sep…); 1 CISA KEV addition (Gitea); 9 critical advisories…"
type: security-digest-day
section: "Security Digest"
date_published: 2026-08-25
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
license: All rights reserved. Quote with attribution and a link.
---

# Security digest: August 25, 2026

2 editorial briefs, 1 known exploited (cisa kev) addition and 9 critical advisories.

## Take stock

- Patch this week: Next.js: Windows, AVIF and next/og RCEs (Aug-Sep 2026) . Teams self-hosting Next.js 13.4+ on Windows, anyone serving the built-in Image Optimization API (next start, standalone, containers) on Next.js 10 through 16.3.2, and Next.js 16.2+ apps that put request data into Node.js next/og images.
- Patch this week: Apache Tomcat August 2026: Security Constraint Bypasses . Anyone running Tomcat 9.0, 10.1 or 11.0, standalone or embedded, that relies on declarative security constraints, FORM or DIGEST authentication, CLIENT-CERT or SPNEGO with DataSourceRealm or JDBCRealm, or RewriteValve rules for access control.
- Do you run any of these? Gitea Gitea. They are being exploited in the wild (CISA KEV). Patch or mitigate if you do; CISA’s federal deadline is 2026-08-28.
- PyPI: 4 critical advisories ( chainlit , qwed-mcp , nextcloud-mcp-server , PraisonAI ). Check with pip-audit (or: pip show <package>) .
- Maven: 3 critical advisories ( org.apache.tomcat:tomcat , org.apache.tomcat:tomcat-catalina , org.apache.tomcat.embed:tomcat-embed-core ). Check with mvn dependency:tree -Dincludes=<groupId>:<artifactId> .
- Hex (Erlang/Elixir): 2 critical advisories ( grpc , ash_authentication ). Check with mix hex.audit .
- None of it touches your stack? Then there is nothing to do today. That is a result, not a failure to read carefully.

## Editorial briefs

- **Patch this week** [Next.js: Windows, AVIF and next/og RCEs (Aug-Sep 2026)](https://erroneo.us/security/briefs/nextjs-windows-avif-next-og-rce/index.md): Self-hosted Next.js apps still below 15.5.24 or 16.3.3 should upgrade now, ideally straight to the October releases; Windows hosts and apps optimizing untrusted AVIF images are the urgent cases.
- **Patch this week** [Apache Tomcat August 2026: Security Constraint Bypasses](https://erroneo.us/security/briefs/apache-tomcat-august-2026-security-constraint-bypasses/index.md): Upgrade Tomcat, including the copy embedded in Spring Boot apps, this week; the access-control bypasses matter wherever you rely on web.xml security constraints or container authentication, and none is known to be exploited.

## Known exploited (CISA KEV)

- [CVE-2026-60004](https://erroneo.us/security/cve/CVE-2026-60004/index.md) Gitea Gitea: Gitea Code Injection Vulnerability (CISA due 2026-08-28)

## Critical advisories

- [CVE-2026-45018](https://erroneo.us/security/cve/CVE-2026-45018/index.md) Chainlit has command injection via MCP stdio transport that allows unauthenticated remote code execution — PyPI chainlit >= 2.4.0rc0, <= 2.11.1 → 2.12.0
- [CVE-2026-55546](https://erroneo.us/security/cve/CVE-2026-55546/index.md) qwed-mcp has Unsafe SymPy `parse_expr()` Remote Code Execution via Unsanitized Math Expression Input — PyPI qwed-mcp < 0.2.1 → 0.2.1
- [CVE-2026-68525](https://erroneo.us/security/cve/CVE-2026-68525/index.md) Apache Tomcat's FORM authentication process has an Incorrect Authorization vulnerability — Maven org.apache.tomcat:tomcat >= 11.0.0-M1, < 11.0.25 → 11.0.25; Maven org.apache.tomcat:tomcat >= 10.1.0-M1, < 10.1.58 → 10.1.58; Maven org.apache.tomcat:tomcat >= 9.0.0-M1, < 9.0.121 → 9.0.121
- [CVE-2026-48853](https://erroneo.us/security/cve/CVE-2026-48853/index.md) gRPC Erlang package vulnerable to Remote Code Execution with attacker-controlled gRPC payloads — Hex (Erlang/Elixir) grpc >= 0.4.0, < 1.0.0 → 1.0.0
- [CVE-2026-65182](https://erroneo.us/security/cve/CVE-2026-65182/index.md) Apache Tomcat has an Improper Access Control, Incorrect Authorization vulnerability — Maven org.apache.tomcat:tomcat >= 11.0.0-M1, < 11.0.25 → 11.0.25; Maven org.apache.tomcat:tomcat >= 10.1.0-M1, < 10.1.58 → 10.1.58; Maven org.apache.tomcat:tomcat >= 9.0.0-M1, < 9.0.121 → 9.0.121
- [CVE-2026-65905](https://erroneo.us/security/cve/CVE-2026-65905/index.md) Apache Tomcat's DIGEST authenticator has an Authentication Bypass by Capture-replay vulnerability — Maven org.apache.tomcat:tomcat >= 11.0.0-M1, < 11.0.25 → 11.0.25; Maven org.apache.tomcat:tomcat >= 10.1.0-M1, < 10.1.58 → 10.1.58; Maven org.apache.tomcat:tomcat >= 9.0.0.M1, < 9.0.121 → 9.0.121
- [CVE-2026-55640](https://erroneo.us/security/cve/CVE-2026-55640/index.md) nextcloud-mcp-server: Unauthenticated `POST /webhooks/nextcloud` allows arbitrary vector data deletion when `WEBHOOK_SECRET` is unset ( default ) — PyPI nextcloud-mcp-server <= 0.117.1 → 0.117.2
- [CVE-2026-49757](https://erroneo.us/security/cve/CVE-2026-49757/index.md) AshAuthentication vulnerable to OAuth2/OIDC account takeover via email-based user matching — Hex (Erlang/Elixir) ash_authentication >= 0.1.0, < 4.14.0 → 4.14.0; Hex (Erlang/Elixir) ash_authentication >= 5.0.0-rc.0, < 5.0.0-rc.10 → 5.0.0-rc.10
- [CVE-2026-55536](https://erroneo.us/security/cve/CVE-2026-55536/index.md) PraisonAI has a Browser Server WebSocket origin validation bypass via unanchored regex (patch bypass of CVE-2026-40289 / GHSA-8x8f-54wf-vv92) — PyPI PraisonAI < 4.6.58 → 4.6.58

---
Source page: https://erroneo.us/security/2026-08-25/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt