Quickly dove into the copy.fail exploit.

1. Yes, it's real.
2. Current chain can write any arbitrary content to any user-readable file (into the page cache).
3. Current chain relies on an available target suid binary that you can open() as a lowpriv user.
4. Current exploit relies on that binary being /bin/su and then being able to execve(/bin/sh, 0, 0) (which doesn't work on alpine, etc.). The former is easily replaced in the code. The latter needs a rebuilt payload ELF (also easy).

Want to make your system immune to copyfail (CVE-2026-31431) but compiled your kernel with CONFIG_CRYPTO_USER_API_AEAD=y so you can’t disable the module and don’t want to reboot? Use BPF-LSM to block AF_ALG sockets from being created!

/* SPDX-License-Identifier: GPL-2.0-or-later OR MIT */

#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>

#define EPERM 1
#define AF_ALG 38

char LICENSE[] SEC("license") = "Dual MIT/GPL";

SEC("lsm/socket_create")
int BPF_PROG(socket_create_block_af_alg, int family, int type, int protocol, int kern, int ret)
{
  if (ret) return ret;          /* don't override a previous denial */
  if (family == AF_ALG) return -EPERM;
  return 0;
}

Compile with clang -Wall -Wextra -Wno-unused-parameter -g -O2 -target bpf -c -o nocopyfail.o nocopyfail.c and load with bpftool prog load nocopyfail.o /sys/fs/bpf/nocopyfail autoattach (as root).

@famfo debian stable/oldstable/oldoldstable seems to still be vulnerable, no new kernel updates... I'll just prevent algif_aead from loading for now

@famfo why, is there a new privilege escalation vulnerability?

@fun @fossdd if someone revives GTK2 then hexchat can be revived too

@fun @fossdd hopefully this will allow hexchat to be packaged in alpine again

I’m not saying I need new electronics but who wouldn’t want a I apologize but I cannot complete this task it requires using trademarked brand names which goes against OpenAI use policy. Is there anything else I can assist you with-16” 32GB RAM

@kemona_halftau meow!

@cwebber @lanodan at least on LCSC the PY32F002AL15S6TU seems to actually be the cheapest currently (ranging from $0.1294 each for 5-50 to $0.083 each for 5000+), whereas couldn't find any CH32V003s for 9 cents: the cheapest is the CH32V003J4M6 at $0.2145 each for 5-50 or $0.1035 each for 5000+

maybe it is available for 9 cents elsewhere though, I only looked on LCSC and the article doesn't specify where

In light of recent events, I just want to put out a PSA

You are seen
You are loved
You are valuable

I’m kind of terrible with words, but I like being here for people. If you ever feel alone, please reach out. I promise there are people who see you and care.

@lanodan @cwebber Puya PY32 is even cheaper and that's ARM: https://jaycarlson.net/2023/02/04/the-cheapest-flash-microcontroller-you-can-buy-is-actually-an-arm-cortex-m0/

Ed Balls

good night

@catsalad for legal reasons I would argue that activitypub is a form of email

@cwebber moaew

@april https://jesterlinux.org/install/ says the USB drive must be ≥4GB but the ISO is 6.7GB

Yay okay so its finally time!
I'm announcing Jester Linux, my own distro based on NixOS for work and gaming, no Nix knowledge required!
https://jesterlinux.org/blog/hello-world/