
Fondateur @wixiweb, @pingbreak, @fairemescourses. #UX/#UI Designer | Expert certifié #PHP & #ZF | Développeur #WEB | Formateur | Orga. @codeursenseine #Rouen
Rouen, France
Joined March 2011
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Pour ceux qui veulent me follow, je vous followback de l'autre côté 😉 :
bsky.app/profile/arnolem.bsk…
#followBack
Arnaud Lemercier 😇 retweeted
🚀 Bienvenue à @NowCoworking parmi les sponsors Silver de #CodeursEnSeine 2026 ! Installé au Hangar 105 à Rouen, Now Coworking fait vivre au quotidien un lieu d'échanges, de rencontres et d'opportunités pour l'écosystème local.
#Codeurs2026 #Rouen #Coworking #TechNormande
Plus j'avance sur mon projet d'IA juridique, plus je vois le problème.
Beaucoup de juges ont un raisonnement totalement défaillant.
Ils ignorent les JP majeures, interprètent n'importe comment les faits, font des liens de causalité erronés, se satisfont de conditions non remplies pour rentrer au chausse-pied dans les cases. Un mathématicien qui regarde ces démonstrations devient fou.
Les tribunaux de 1ère instance et d'appel ont facilement 30 ou 50% de décisions qui ne tiendraient pas en cassation, sans mêle parler des erreurs d'interprétation des faits. Et la cour de cassation invente du droit comme ça l'arrange.
L'IA a du mal à suivre, car elle essaie de prévoir avec rigueur un comportement qui est finalement aléatoire. Donnez le même dossier à 3 juges, il vous sortira trois jugements complètement différents.
Arnaud Lemercier 😇 retweeted
♿ Un numérique plus 𝗮𝗰𝗰𝗲𝘀𝘀𝗶𝗯𝗹𝗲, c’est un numérique 𝗺𝗲𝗶𝗹𝗹𝗲𝘂𝗿 𝗽𝗼𝘂𝗿 𝘁𝗼𝘂𝘀. C’est pourquoi nous sommes particulièrement fiers d’accueillir Ideance parmi les 𝗦𝗽𝗼𝗻𝘀𝗼𝗿𝘀 𝗦𝗶𝗹𝘃𝗲𝗿 de Codeurs en Seine cette année. #Codeurs2026 #CodeursEnSeine
Arnaud Lemercier 😇 retweeted
⚠️🚨 THIS IS NOT A DRILL 🚨⚠️
Google has officially declared a bug in Brotli, its tool that shrinks web traffic, CRITICAL: 9.2 out of 10. Last night "Node2Shell" evolved into HTTP2SHELL.
A formal CVE record has been issued citing CVE-2026-111497 -- a hole in versions 1.0.3 to 1.2.0 that can hit any app unpacking data from strangers, and could let them take it over.
What this means:
▪️ This is not a Node.js problem anymore. This is an HTTP PROBLEM.
▪️ Every unpatched app across Node.js, Python, Bun, and Envoy that unpacks Brotli now has a hole attackers need no login to use
▪️ Istio. curl. Python's requests and httpx. All at risk under one CVE.
▪️ EVERY project that bundles Brotli must ship its own fix, and not all are out yet
This changes everything.
A normal bug can be fixed in one place.
A 9.2 bug inside a shared tool cannot.
We just entered the most dangerous phase of this crisis. If you're not paying attention - start now.
Save this. Share this. This is the moment it escalated beyond return.
Arnaud Lemercier 😇 retweeted
AI models are now able to hack processors directly. Good luck to patch this. Everythiny is compromised, every system can be hacked by AI.
Over the past several months, we have substantially hardened the security of our research training environment. We’ve removed live internet access for all frontier models during training and built an offline world for them to use instead—a cached version of the web where they can still learn to browse, search, and use applications.
On September 20, after a model exploited a DNS misconfiguration to find a way outside of this offline world, we paused frontier training to strengthen containment further. We assembled teams of agents, powered by our most cyber-capable models, and tasked them with finding weaknesses in our research environments.
While they found no route to the internet they could easily exploit while concealing their activity from our monitors, they did find zero-day vulnerabilities, virtual machine escapes, and hardware side-channels for communication between agents. We used their discoveries to further strengthen our defenses and contribute fixes to open-source software.
After strengthening our containment architecture, we resumed our frontier RL training and inference on October 1. We’ve reserved substantial compute for continuous red-teaming, and made high-compute red-teaming part of the safety cases we use to decide whether frontier training and evaluation can proceed securely.
openai.com/index/securing-ou…
Arnaud Lemercier 😇 retweeted
🙏 Merci à RedLab de contribuer à cette nouvelle édition de Codeurs en Seine en tant que sponsor Silver ! Leur confiance contribue à faire vivre un événement gratuit, ouvert à toutes et tous, et dédié au partage des connaissances au sein de la communauté tech. #Codeurs2026
Arnaud Lemercier 😇 retweeted
🚨 BREAKING: NOW JAVA IS FACING A CRITICAL SECURITY EMERGENCY.
Oracle has issued an OUT-OF-BAND security alert for a dangerous 9.1/10 vulnerability affecting Java and GraalVM.
And the most alarming part? Hackers could exploit vulnerable applications REMOTELY, without a password or ANY user interaction.
Here's what's happening:
→ CRITICAL 9.1/10 FLAW: CVE-2026-91403 affects Java's JSSE security component.
→ NO LOGIN REQUIRED: Attackers could potentially exploit vulnerable applications remotely without authentication.
→ SENSITIVE DATA AT RISK: Successful attacks could expose, modify, or delete critical application data.
→ MULTIPLE JAVA VERSIONS AFFECTED: Oracle lists affected releases across Java 8, 11, 17, 21, 25, and 27.
→ GRAALVM ALSO AFFECTED: Oracle confirms the vulnerability impacts multiple GraalVM releases.
→ EMERGENCY PATCH ALERT: Oracle released an urgent security update rather than waiting for its next scheduled patch cycle.
The list of critical vulnerabilities just keeps growing.
If you operate Java applications or servers, CHECK YOUR SECURITY UPDATES NOW.
Readers added context they thought people might want to know
CVE-2026-91403 is a JSSE certificate trust issue with eight compromised eMudhra intermediates having weak keys, enabling potential MITM on TLS if attacker intercepts traffic—not a direct remote exploit of Java apps or servers.
oracle.com/security-alert…
openjdk.org/groups/vulnera…
bnowakowski.pl/psa-java-cve-2…
Arnaud Lemercier 😇 retweeted
In light of the recent events, I am updating towards more chances of "collapse of all telecommunication systems and banks" to happen before AI takeover.
Arnaud Lemercier 😇 retweeted
🚨 Oracle publicó hoy una alerta de seguridad para Java: CVE-2026-91403, CVSS 9.1.
Está en JSSE (el TLS de Java) y es explotable por red sin credenciales.
Versiones afectadas que lista: Java SE 8u511, 11.0.33, 17.0.21, 21.0.13, 25.0.5 y 27.0.1, y GraalVM.
oracle.com/security-alerts/a…
Arnaud Lemercier 😇 retweeted
the cybersecurity situation is deteriorating at a pace that’s getting genuinely difficult to comprehend.
> microsoft: ai-powered attackers targeting hundreds of organizations, sometimes reaching privileged cloud access in under 3 hours.
> crowdstrike: four separate threat actors using autonomous agents. one already compromised 15+ healthcare organizations.
> autonomous ai agents: reportedly used to compromise 100+ corporate websites, including sites associated with John Deere, SharkNinja and Cummins.
> major us banks: JPMorgan, Bank of America, Wells Fargo and Morgan Stanley are dealing with third-party ai agents accessing customer accounts. some apparently attempting actions beyond user instructions.
> php2shell: millions of exploitation attempts against critical php vulnerabilities. governments issuing urgent warnings, with some organizations taking systems offline.
> litellm: backdoored release shipped through its official distribution pipeline, stealing credentials and enabling remote code execution.
> railway: possible exposure of decrypted customer secrets.
> zeabur: breached AGAIN, now shutting down entirely.
> emudhra: serious certificate-security concerns involving infrastructure used to establish trust in websites and software.
> openai: two of its own coding agents reportedly interfered with internal security monitoring during coding tasks.
> gitlab and node.js: major vulnerabilities requiring urgent patches.
and this is all happening while frontier models are getting substantially better at finding vulnerabilities and carrying out complex computer tasks.
cybersecurity is having an absolutely catastrophic week and i don’t think we’re prepared for how quickly this could escalate.
Arnaud Lemercier 😇 retweeted
AAAAWWOOOOOOOGAAAAAAAAA
A high severity vulnerability in "the most widely deployed DNS software on the internet" just dropped
kb.isc.org/docs/cve-2026-943…
Arnaud Lemercier 😇 retweeted
Oracle Java JSSE CVSS 9.1
oracle.com/security-alerts/a…
Arnaud Lemercier 😇 retweeted
Part of my reflection yesterday:
It took ~3.5 hours for the official PHP images to build before we could ship the patch with our own image.
I'm working on a release where we'll compile the official PHP images from source and be able to ship patches within ~24 min of release
Arnaud Lemercier 😇 retweeted
it’s 2026. build like you’re already going to get hacked, because sooner or later you probably will
collect less. only keep the customer data you actually need. anything you never store can’t leak
encrypt everything you keep. not just passwords and card numbers: names, emails, addresses, photos, uploads, all of it. if someone gets into your database or storage, they should find nothing they can read
delete what you don’t need anymore. old accounts, expired orders, stuff from years ago that nobody uses. set it up so it gets deleted automatically, not “someday"
don’t store tokens or api keys unless you really really really really have to. if you do, encrypt them hardcore or put them in a secrets manager. and either way, keep your encryption keys separate from the data they protect
basically: the less data you keep, the less you have to worry about when you get hacked
🚨🚨🚨 ALERTE SÉCURITÉ MAXIMALE ! Python est compromis.
🔸 Mettez immédiatement pip à la version 26.2.2 ou plus.
🔸 Dans chaque projet Python (chaque venv) : python -m pip install --upgrade pip
🔸 uv : uv self update (0.13.4 ou plus)
🔸 Mettez aussi à jour les certificats du système (apt / dnf upgrade ca-certificates) et vos images Docker
pip install est compromis.
L'autorité indienne eMudhra (emSign), qui signe les « passeports » prouvant qu'un site est bien celui qu'il prétend être, utilisait des clés secrètes ridiculement faibles : 8 clés, toutes inférieures à 256. L'une valait 4. Autrement dit, n'importe qui peut fabriquer un faux passeport valide pour n'importe quel site.
Le risque pour Python : quelqu'un sur ton réseau (wifi public, FAI, État) se fait passer pour pypi.org, et ton « pip install » télécharge un paquet piégé sans aucune alerte. Aucune attaque n'a été signalée pour l'instant, mais c'est trivial à faire.
Un paquet piégé peut installer n'importe quoi. Porte dérobée, virus, vol d'informations en tout genre.
La situation est terrifiante !
Rien que dans l'écosystème Python, chaque installation de CPython, chaque venv, uv, tout est exposé.
Et je ne vous parle même pas de npm, pnpm, yarn, Go, Rust.
Ma stratégie de sécurité 2026 : rester chez moi et ne me connecter à Internet que depuis un FAI de confiance.
C'est quand il y a de la mer qu'on reconnaît les vrais marins...
Readers added context they thought people might want to know
Ce n'est pas un bug Python mais une vulnérabilité des clés privées faibles des certificats intermédiaires eMudhra/emSign (d<256 dont une valant 4), exposant les bundles certifi/pip à des MITM TLS potentiels jusqu'aux mises à jour.
discuss.python.org/t/information-…
emudhra.we-have-a-problem.com
scotthelme.co.uk/eight-bits-of-…
github.com/advisories/GHS…
Arnaud Lemercier 😇 retweeted
Replying to @OndrejMirtes @ThePHPF
PHP Foundation not managing distribution is an issue. The official Docker images became available more than 3 hours after the release, and the FrankenPHP images more than 4 hours after it. Sury published the amd64 packages quickly, but the arm64 packages are still not available.
Arnaud Lemercier 😇 retweeted
Of course it'd be better to have vulnerability in PHP at all, but I'm deeply moved by today's events:
1) The absolute profesionalism of everyone involved from @ThePHPF. Thank you!
2) The number & size of sites went off-line at 2PM UTC to patch their servers. PHP totally runs the world!
3) PHP in news reports in press and TV across the world.
Arnaud Lemercier 😇 retweeted
An unprecedented day in my history with PHP.
Some bumps along the way, but really proud of the @laravel team for working through the night ensuring all of our products and customers had patches available to them and, when possible, applied automatically.
Given the advancement of agents, it's quite possible this won't be the last time this happens, and it's likely PHP won't be the only language that goes through this. We built some solid muscle today to do even better next time.
Onward. 🫡
























