Uploaded March 2023 | Updated September 2026, 2 weeks ago
This 2023 update explained how German students could participate in the Cyber Security Challenge Germany, qualify for the European Cyber Security Challenge, meet other young hackers, and help build the community.
LEARN ON HEXTREE (ad)
Learn hacking on Hextree: hextree.io
Join the Hextree Discord: discord.gg/xgQpCQCpvy
CSCG: cscg.de
Donate to NFITS: nfits.de/spenden
CSCG Aftermovie: youtube.com/watch?v=GZmCObcHoGw
ECSC: https://ecsc.eu/
Intro Rev Video: youtube.com/watch?v=28JHPOUZvDw
Intro Pwn Video: youtube.com/watch?v=hhu7vhmuISY
Get started with hacking: liveoverflow.com/faq/get-started-with-hacking
CHAPTERS
00:00 - CSCG and the European competition
01:04 - How qualification and age divisions work
02:03 - Scoreboards and dynamic scoring
03:44 - Challenge categories and beginner progression
05:22 - Learning and networking on Discord
07:00 - The nonprofit behind CSCG
08:33 - Donations and industry partnerships
10:06 - Time left and the finals opportunity
10:59 - Competitions in other European countries
12:15 - My CSCG experience and CTF teams
13:17 - Ways to participate and support the event
SUPPORT
Per video: patreon.com/join/liveoverflow
Per month: youtube.com/channel/UClcE-kVhqyiHCcjYwcpfj9w/join
Buy my handwriting font (ad): shop.liveoverflow.com
WATCH, FOLLOW & READ
Second channel: youtube.com/LiveUnderflow
Twitch: twitch.tv/LiveOverflow
Twitter: twitter.com/LiveOverflow
Instagram: instagram.com/LiveOverflow
TikTok: tiktok.com/@liveoverflow_
LiveOverflow blog: liveoverflow.com
Hextree blog (ad): hextree.io/blog
#CTF #CSCG #LiveOverflow
(ad) LiveOverflow YouTube channel is supported by advertisement and product placement.
This 2023 update explained how German students could participate in the Cyber Security Challenge Germany, qualify for the European Cyber Security Challenge, meet other young hackers, and help build the community.
LEARN ON HEXTREE (ad)
Learn hacking on Hextree: hextree.io
Join the Hextree Discord: discord.gg/xgQpCQCpvy
CSCG: cscg.de
Donate to NFITS: nfits.de/spenden
CSCG Aftermovie: youtube.com/watch?v=GZmCObcHoGw
ECSC: https://ecsc.eu/
Intro Rev Video: youtube.com/watch?v=28JHPOUZvDw
Intro Pwn Video: youtube.com/watch?v=hhu7vhmuISY
Get started with hacking: liveoverflow.com/faq/get-started-with-hacking
CHAPTERS
00:00 - CSCG and the European competition
01:04 - How qualification and age divisions work
02:03 - Scoreboards and dynamic scoring
03:44 - Challenge categories and beginner progression
05:22 - Learning and networking on Discord
07:00 - The nonprofit behind CSCG
08:33 - Donations and industry partnerships
10:06 - Time left and the finals opportunity
10:59 - Competitions in other European countries
12:15 - My CSCG experience and CTF teams
13:17 - Ways to participate and support the event
SUPPORT
Per video: patreon.com/join/liveoverflow
Per month: youtube.com/channel/UClcE-kVhqyiHCcjYwcpfj9w/join
Buy my handwriting font (ad): shop.liveoverflow.com
WATCH, FOLLOW & READ
Second channel: youtube.com/LiveUnderflow
Twitch: twitch.tv/LiveOverflow
Twitter: twitter.com/LiveOverflow
Instagram: instagram.com/LiveOverflow
TikTok: tiktok.com/@liveoverflow_
LiveOverflow blog: liveoverflow.com
Hextree blog (ad): hextree.io/blog
#CTF #CSCG #LiveOverflow
(ad) LiveOverflow YouTube channel is supported by advertisement and product placement.






![A Vulnerability to Hack The World - CVE-2023-4863
Citizenlab discovered BLASTPASS, a 0day being actively exploited in the image format WebP. Known as CVE-2023-4863 and CVE-2023-41064, an issue in webps build huffman table function can lead to a heap buffer overflow. This vulnerability is very interesting and Im excited to share with you what I learned.
LEARN ON HEXTREE (ad)
Learn hacking on Hextree: https://www.hextree.io/
Join the Hextree Discord: https://discord.gg/xgQpCQCpvy
WebP Fix Commit: https://chromium.googlesource.com/webm/libwebp/+/902bc9190331343b2017211debcec8d2ab87e17a
Citizenlab: https://citizenlab.ca/2023/09/blastpass-nso-group-iphone-zero-click-zero-day-exploit-captured-in-the-wild/
Ben Hawkes: https://blog.isosceles.com/the-webp-0day/
Software Updates
Apple https://support.apple.com/en-gb/106361
Chrome https://chromereleases.googleblog.com/2023/09/stable-channel-update-for-desktop_11.html
Firefox https://www.mozilla.org/en-US/security/advisories/mfsa2023-40/
Android https://source.android.com/docs/security/bulletin/2023-10-01
Whose CVE is it Anyway? https://adamcaudill.com/2023/09/14/whose-cve-is-it-anyway/
References:
2014 bug introduction https://github.com/webmproject/libwebp/commit/f75dfbf23d1df1be52350b1a6fc5cfa6c2194499
https://www.youtube.com/watch?v=JsTptu56GM8
https://www.youtube.com/watch?v=B3y0RsVCyrw
https://www.youtube.com/watch?v=EFUYNoFRHQI
https://www.youtube.com/watch?v=iEm1NRyEe5c
https://stackoverflow.com/questions/13804629/huffman-code-with-lookup-table
https://web.archive.org/web/20230204211844/https://commandlinefanatic.com/cgi-bin/showarticle.cgi?article=art007
enough.c https://github.com/madler/zlib/blob/develop/examples/enough.c
Thanks to:
https://twitter.com/mistymntncop
https://twitter.com/benhawkes
CHAPTERS
00:00 - Intro to CVE-2023-4863
01:32 - Most Valuable Vulnerability?
03:02 - Heap Overflow Related to Huffman Trees
03:58 - Learning about Huffman Codes
06:24 - What are Huffman Tables?
10:24 - Hardcoded Table Sizes (enough.c)
12:21 - Code Walkthrough - BuildHuffmanTable()
13:04 - The code_lengths[] and count[] Arrays
15:14 - Difference Between Compression and Decompression!
17:04 - Outro
SUPPORT
Per video: https://www.patreon.com/join/liveoverflow
Per month: https://www.youtube.com/channel/UClcE-kVhqyiHCcjYwcpfj9w/join
Buy my handwriting font (ad): https://shop.liveoverflow.com/
WATCH, FOLLOW & READ
Second channel: https://www.youtube.com/LiveUnderflow
Twitch: https://twitch.tv/LiveOverflow/
Twitter: https://twitter.com/LiveOverflow/
Instagram: https://instagram.com/LiveOverflow/
TikTok: https://www.tiktok.com/@liveoverflow_
LiveOverflow blog: https://liveoverflow.com/
Hextree blog (ad): https://www.hextree.io/blog
#BufferOverflow #SecurityResearch #LiveOverflow
(ad) LiveOverflow YouTube channel is supported by advertisement and product placement. A Vulnerability to Hack The World - CVE-2023-4863](https://i.ytimg.com/vi/lAyhKaclsPM/mqdefault.jpg)



