Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Clear out junk files and repair common Windows errors3Fix the driver behind crashes, sound loss and screen glitchesIn the documented picoCTF 2022 Buffer Overflow 1 binary, the demonstrated offset from the input buffer to saved EIP is 44 bytes. The example payload is 44 padding bytes followed by the little-endian address of win(), 0x080491f6. Those values apply only to that specific 32-bit binary: inspect and verify your own challenge artifact before using them.
What the challenge is asking you to do
The 2022 challenge source reproduced in the CTFtime writeup declares a 32-byte local buffer and reads into it with gets(), which does not limit input to the buffer’s capacity. It also defines win(), which opens flag.txt and prints its contents. The intended control-flow change is to supply enough input to overwrite the saved return address so the vulnerable function returns to win(). CTFtime’s picoCTF 2022 Buffer Overflow 1 writeup
The source’s 32-byte buffer size is not the return-address offset. Stack layout and other saved data affect the distance between the buffer and saved EIP, so measure that distance in the actual binary rather than assuming it equals the declared buffer size.
Measure and verify the binary-specific values
- Identify the exact challenge edition and artifact. Confirm that you have the 2022 Buffer Overflow 1 binary, not a similarly named challenge from another year.
- Inspect the target. Check its architecture and endianness, locate the vulnerable input and the target function (
winin the cited 2022 example), and determine whether the binary’s mitigations or layout differ from the example. - Measure the offset to saved EIP. Use a debugger such as GDB to establish the distance from the start of the input buffer to the saved instruction pointer. Do not infer the offset from the buffer declaration alone.
- Use the address from your binary. Obtain the target function’s address from the supplied artifact, then encode it in the target architecture’s byte order. The 2022 example is i386, so its address is represented little-endian.
- Test locally before using an authorized challenge service. Confirm that execution reaches the intended function with the measured offset and address. If running locally, note that the example source has a fallback message when
flag.txtis unavailable; a local test file may be needed to see file-reading behavior.
The documented 2022 example payload
For the particular binary shown in the CTFtime writeup, the buffer begins at 0xffffd050 and saved EIP is at 0xffffd07c, a difference of 44 bytes. The writeup reports a 32-bit i386 binary with no stack canary, NX disabled, and no PIE. Its win() address is 0x080491f6, printed there as 0x80491f6.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Accordingly, the payload structure for that artifact is:
[44 padding bytes] + [win() address as four little-endian bytes]
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
The address bytes are xf6x91x04x08. In a pwntools-style Python expression, the example structure is b'A' * 44 + p32(0x080491f6). Use this only if your own binary’s measured offset, architecture, byte order, and function address match. A changed build or challenge instance can invalidate one or more values.
Do not mix it up with the 2019 Overflow 1 challenge
A separate picoCTF 2019 challenge writeup uses a different program: it has a 64-byte buffer, targets a function named flag(), and derives a 76-byte offset. Its binary addresses also differ. These are not alternate values for the 2022 challenge. CTFtime’s picoCTF 2019 Overflow 1 writeup
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
| Challenge example | Buffer size in cited source | Demonstrated offset | Target function | Address |
|---|---|---|---|---|
| picoCTF 2022 Buffer Overflow 1 | 32 bytes | 44 bytes | win() |
0x080491f6 in the cited binary |
| picoCTF 2019 Overflow 1 | 64 bytes | 76 bytes | flag() |
Different binary-specific address; not stated here |
Why the exercise matters
Return-address overwrites illustrate how unsafe input handling can affect program control flow. picoCTF’s 2018 educational outcomes identify buffer-overflow exploitation and controlling execution by overwriting return addresses as learning goals, alongside debugging with GDB and studying mitigations such as canaries, ASLR, and NX. The document describes educational objectives; it does not establish that a particular challenge endpoint is currently available. picoCTF educational resources
Quick Recap
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
