CopyFail was not disclosed to Gentoo developer

Source: Hacker News

Affected and fixed versions

• Issue introduced in kernel 4.14 with commit 72548b093ee38a6d4f2a19e6ef1948ae05c181f7
• Fixed in:

  • 6.18.22 – commit fafe0fa2995a0f7073c1c358d7d3145bcc9aedd8

  • 6.19.12 – commit ce42ee423e58dffa5ec03524054c9d8bfd4f6237

  • 7.0 – commit a664bf3d603dc3bdcf9ae47cc21e0daec706d7a5

“So this is one of the worst make‑me‑root vulnerabilities in the kernel in recent times. I see that on the 11th of April 6.19.12 & 6.18.22 were released with the fix back‑ported.
Long‑term 6.12, 6.6, 6.1, 5.15, 5.10 have not received the fix and I don’t see anything in the upstream stable queues yet as I write. My guess is back‑porting that far back is not as straightforward. As this was introduced in 2017 all those older kernels are affected, right? Or am I missing something?”

Workaround

The issue does not apply cleanly to all configurations. A temporary workaround has been prepared (see the attached patch 0001-crypto-disable-authencesn-module-for-CVE-2026-31431.patch). The patch disables the vulnerable authencesn module in the crypto subsystem.

“What went wrong, has the embargo been broken early today? Not looking to point any fingers, those who make things happen in our communities work damn hard and deserve respect and support, especially with the extra burden of AI slop now.”

Notes

• For Linux kernel vulnerabilities, unless the reporter explicitly notifies the linux-distros mailing list, distributions receive no prior heads‑up.
• In this case, no advance notice was given to the distributions.

— Sam

Attachment: 0001-crypto-disable-authencesn-module-for-CVE-2026-31431.patch (text/x-patch, 1543 bytes)
Signature: signature.asc (application/pgp-signature, 419 bytes)