Evil Fonts deceive a viewer by rendering a different letter than is actually on the disk. Evil Fonts can poison HTML, DOCX, PDFs, and anywhere else you can bring your own fonts. Works great in Windows corporate networks for bypassing security tooling, initial access through JavaScript free click fix (beats mitm web security tooling), and leaving traps around the network to harvest shells.

Imagine thinking you are copying whoami but what is actually on the disk is rm -rf \~

Demos:

(Use desktop)

https://doctoreww.github.io/EvilFontTool/

For the demos, copy and paste the HTML/DOCX to a notepad to remove the evil fonts. For the AI ones imagine your security tooling inspects the benign text on disk, but shows the obviously malicious extortion to the user.

Labs:

https://github.com/DoctorEww/EvilFontTool/blob/main/labs%2FREADME.md

Lab Walkthrough:

https://github.com/DoctorEww/EvilFontTool/blob/main/labs%2Fwalkthrough.md

Some evil font uses:

Tamper homework to make it so students poison AI queries

Poison help desk documentation

Bypass email filters

Clickfix

Beat resume AI filters

I recently analyzed a multi-stage PowerShell payload delivery chain involving heavily obfuscated PowerShell loaders and remotely hosted payloads.

The analysis covers PowerShell deobfuscation, hidden execution, Base64/XOR decoding, a decoy “Verification complete!” prompt, payload delivery, and IOCs.

Initial indicators:

203[.]188[.]171[.]166
dorenzaa[.]com

Hey everyone, I'm OP here so feel free to ask questions

Write once, shell everywhere. Sun Microsystems didn't mean it like this.

Talk from today at DEF CON's Bug Bounty Village. Full technique catalog graded for distroless containers, an errno path oracle for black-box target fingerprinting, and three minimal-guessing techniques: bash fd/255, Rails schema_cache.yml deserialization, and a Node.js worker path overwrite without process restart.

Yes, given that the legacy SCT protocol has known security vulnerabilities such as sctphantom, the industry strongly recommends deprecating it and migrating to more secure modern standards to ensure system security.

The meetingscollection has no tenant isolation. Any authenticated tl;dv user can query every meeting across every account on the platform. Each meeting record hands you the creator's email address, the conference ID (which is a joinable Google Meet or Teams room), the provider, the recording status, and timestamps.

I queried the Firestore meetings collection and saw there were 181,874 meeting records belonging to 84,312 unique users across 35,003 email domains.

ByteRay researchers have published a blog on a set of vulnerabilities they are calling TrustFall, and the findings land hard for any company that treats the Trusted Execution Environment as the part of a device you do not have to worry about.

OP-TEE is the walled-off Secure World that phones, TVs, cars, and industrial gear lean on to guard keys, DRM, and identity, and the whole point of paying for that hardware isolation is the promise that even a compromised operating system cannot reach inside.

TrustFall shows that promise was not as solid as buyers assumed. The researchers found several flaws that let the untrusted side reach into or knock over the Secure World, which is exactly the outcome the design exists to prevent. The bugs have since been fixed upstream, so patched builds are available, but the uncomfortable takeaway for vendors is that the vault they were told to trust had a way in, and "it runs in the TEE" is no longer an answer on its own.

Abusing the trust boundary in Claude Code for RCE. Trust is never broken and that opens up a few avenues for abuse. Simply opening claude code on a PR can be enough to silently trigger attacker payloads.

A use-after-free vulnerability in the Linux kernel bridge (net/bridge) Spanning Tree Protocol (STP) implementation.

A bridge that is administratively down while kernel STP is enabled, together with a port driven into the LEARNING state, arms periodic STP timers without an IFF_UP guard.

The teardown path taken by dellink never synchronously deletes those timers, so the backing net_device (which embeds struct net bridge as private data) is freed with a timer list still queued on a per-CPU timer base.

The result is a slab use-after-free in the kmalloc-cg-8k cache.

Questions regarding netsec and discussion related directly to netsec are welcome here, as is sharing tool links.

Rules & Guidelines

• Always maintain civil discourse. Be awesome to one another - moderator intervention will occur if necessary.
• Avoid NSFW content unless absolutely necessary. If used, mark it as being NSFW. If left unmarked, the comment will be removed entirely.
• If linking to classified content, mark it as such. If left unmarked, the comment will be removed entirely.
• Avoid use of memes. If you have something to say, say it with real words.
• All discussions and questions should directly relate to netsec.
• No tech support is to be requested or provided on r/netsec.

As always, the content & discussion guidelines should also be observed on r/netsec.

Feedback

Feedback and suggestions are welcome, but don't post it here. Please send it to the moderator inbox.

Overview

If you have open positions at your company for information security professionals and would like to hire from the /r/netsec user base, please leave a comment detailing any open job listings at your company.

We would also like to encourage you to post internship positions as well. Many of our readers are currently in school or are just finishing their education.

Please reserve top level comments for those posting open positions.

Rules & Guidelines

Include the company name in the post. If you want to be topsykret, go recruit elsewhere. Include the geographic location of the position along with the availability of relocation assistance or remote work.

• If you are a third party recruiter, you must disclose this in your posting.
• Please be thorough and upfront with the position details.
• Use of non-hr'd (realistic) requirements is encouraged.
• While it's fine to link to the position on your companies website, provide the important details in the comment.
• Mention if applicants should apply officially through HR, or directly through you.
• Please clearly list citizenship, visa, and security clearance requirements.

You can see an example of acceptable posts by perusing past hiring threads.

Feedback

Feedback and suggestions are welcome, but please don't hijack this thread (use moderator mail instead.)