Fixed/disclosed vulnerabilities, auth bugs, hardening, CVE write-ups.
In a red-team exercise our support agent read a customer-uploaded PDF with hidden instructions and drafted an email with another customer's order details. No data left the building, but the flaw was real. How we contained it with least privilege, confirmation and output checks.
The pre-launch security checklist we run on every new web app, organised by the OWASP Top 10:2025 categories: authorization tests, injection, secrets, headers and CSP, supply chain, error handling and logging, each with a concrete check you can automate.
A customer saw a snippet from another company's document in an AI answer. A new 'related questions' feature queried the vector store through a helper that did not apply the tenant filter. We moved tenant scoping into the repository layer so no code path can skip it.
A customer changed the number in an invoice download URL and got someone else's PDF. The endpoint looked up invoices by sequential ID with no ownership check. We scoped every query to the account, added an object policy and cross-tenant tests.
Prompt and response logs are the fastest way to build an accidental PII database. This guide shows where personal data enters an LLM feature, how to redact it before logging and before the provider, and how to keep retention and access under control.
Our partner OAuth server matched redirect_uri by prefix, and our login page followed any next URL. Chained together with a legacy implicit flow, an access token could land on an outside domain. We moved to exact matching, relative-only next and code plus PKCE.
GitOps says everything lives in Git, and secrets are the exception that breaks the rule. This guide compares encrypting secrets in Git with SOPS or Sealed Secrets against referencing them from a secret manager with External Secrets Operator or the CSI driver, including rotation and bootstrap.
Every value in our orders API was a bound parameter, except the sort column, which was pasted into ORDER BY from the query string. A pentest proved it was injectable. We replaced it with an allowlist map and added tests that fuzz the sort input.
A practical guide to cookie attributes for engineers who keep getting logged out of embedded widgets or failing security reviews: what SameSite, Secure, HttpOnly, __Host- and Partitioned really do, with tested defaults for common setups.
A pull request added a dependency that an AI assistant had suggested. The package name did not exist when the code was written, and a few weeks later someone else published it. We caught it in review by luck, then added registry checks so we do not rely on luck.
Our comment system rendered Markdown and stripped script tags, yet a link with a javascript: URL survived into the page. We fixed it by sanitizing the rendered HTML with an allowlist of tags, attributes and URL schemes, and backed it with a strict Content-Security-Policy.
An internal audit found a workflow that used pull_request_target to post preview links and also checked out the pull request's code and ran npm install. Any fork PR could have run code with our deploy token. We split it into an unprivileged build and a privileged comment step.
An exchange API key with withdrawal rights on a bot host is a hot wallet with extra steps. This guide covers the controls we use for trading bot keys: least-privilege permissions, IP allowlists, sub-accounts, secret storage, rotation, logging without leaking signatures, and incident response.
Every POST to our Django admin returned 403 after we moved TLS termination to a Traefik ingress. Django compared the browser's https Origin with a request it believed was plain http. Two settings fixed it without weakening CSRF.
In March 2025 the popular tj-actions/changed-files action was compromised and its version tags were repointed to code that printed CI secrets into workflow logs. Three of our repositories used it by tag. This is how we checked exposure, rotated secrets and moved to SHA pinning.
After upgrading to PyTorch 2.6, every checkpoint load in our evaluation pipeline failed with Weights only load failed. The default for weights_only in torch.load flipped to True, and our checkpoints contained a NumPy scalar. We fixed the checkpoints instead of turning the safety off.
Our PayPal checkout button rendered in development and staging but was an empty box in production. A new Content-Security-Policy set in Nginx blocked the PayPal SDK script, its iframes and its API calls. We fixed it per directive, with a nonce and a report-only rollout.
A developer committed a .env file with a live AWS access key, then deleted it in the next commit. The key stayed in history. We revoked it within 40 minutes, checked CloudTrail, rewrote history with git filter-repo and added scanning so it cannot happen again.
Our API certificate renewal looked perfect in desktop Chrome, yet the Android app, curl and a partner's Java service all rejected it. The server sent only the leaf certificate without the intermediate. Serving the full chain fixed every client at once.
An internal reporting service read the user ID and role from a JWT with jwt.decode(), which never checks the signature. A route that bypassed our gateway let any edited token through. We switched to verification with a pinned algorithm, issuer, audience and JWKS rotation.
Our deploy job worked on main and failed on the production environment with Not authorized to perform sts:AssumeRoleWithWebIdentity. Using a GitHub environment changes the OIDC subject claim. We rewrote the trust policy around exact subjects instead of wildcards.