[Go 1.23.0] CVE-2026-39832: ssh/agent: reject keys with unsupported confirm constraint

[Atharva-Shinde]

Process

# branch_setup.py — checked out upstream/sustaining-v0.41.0
# git am failed — patch context mismatch, user resolved manually

Conflicts

• ssh/agent/keyring.go: Patch expected ConstraintExtensions rejection check to already exist — v0.41.0 does not have it. User applied ConfirmBeforeUse check manually.
• ssh/agent/keyring_test.go: Patch expected TestAddKeyWithConstraintExtensions test — not present in v0.41.0. User added new test manually.

Patch Source

https://go-review.googlesource.com/changes/crypto~778642/revisions/3/patch?download&raw

v0.41.0-GO-2026-5006-0.patch

Verification

Runtime gates: none

Unit tests output

crypto git:(sustaining-v0.41.0) go test ./...
?       golang.org/x/crypto/acme/autocert/internal/acmetest  [no test files]
?       golang.org/x/crypto/acme/internal/acmeprobe [no test files]
?       golang.org/x/crypto/cryptobyte/asn1     [no test files]
?       golang.org/x/crypto/internal/testenv    [no test files]
?       golang.org/x/crypto/internal/wycheproof/internal/dsa [no test files]
?       golang.org/x/crypto/openpgp/errors      [no test files]
ok      golang.org/x/crypto/acme        9.473s
ok      golang.org/x/crypto/acme/autocert       3.739s
ok      golang.org/x/crypto/argon2      4.389s
ok      golang.org/x/crypto/bcrypt      2.253s
ok      golang.org/x/crypto/blake2b     3.931s
ok      golang.org/x/crypto/blake2s     2.614s
ok      golang.org/x/crypto/blowfish    1.790s
ok      golang.org/x/crypto/bn256       5.340s
ok      golang.org/x/crypto/cast5       2.823s
ok      golang.org/x/crypto/chacha20    3.051s
ok      golang.org/x/crypto/chacha20poly1305    1.385s
ok      golang.org/x/crypto/cryptobyte  4.803s
ok      golang.org/x/crypto/curve25519  5.600s
ok      golang.org/x/crypto/ed25519     6.005s
ok      golang.org/x/crypto/hkdf        5.058s
ok      golang.org/x/crypto/internal/alias      5.105s
ok      golang.org/x/crypto/internal/poly1305   5.045s
ok      golang.org/x/crypto/internal/wycheproof 6.581s
ok      golang.org/x/crypto/md4 5.322s
ok      golang.org/x/crypto/nacl/auth   5.648s
ok      golang.org/x/crypto/nacl/box    5.232s
ok      golang.org/x/crypto/nacl/secretbox      5.459s
?       golang.org/x/crypto/poly1305    [no test files]
ok      golang.org/x/crypto/nacl/sign   5.457s
ok      golang.org/x/crypto/ocsp        5.495s
ok      golang.org/x/crypto/openpgp     6.432s
ok      golang.org/x/crypto/openpgp/armor       5.477s
?       golang.org/x/crypto/ssh/terminal        [no test files]
ok      golang.org/x/crypto/openpgp/clearsign   14.068s
ok      golang.org/x/crypto/openpgp/elgamal     5.432s
ok      golang.org/x/crypto/openpgp/packet      5.404s
ok      golang.org/x/crypto/openpgp/s2k 6.399s
ok      golang.org/x/crypto/otr 5.081s
ok      golang.org/x/crypto/pbkdf2      4.882s
ok      golang.org/x/crypto/pkcs12      5.023s
ok      golang.org/x/crypto/pkcs12/internal/rc2 5.191s
ok      golang.org/x/crypto/ripemd160   5.484s
ok      golang.org/x/crypto/salsa20     5.870s
ok      golang.org/x/crypto/salsa20/salsa       5.837s
ok      golang.org/x/crypto/scrypt      5.878s
ok      golang.org/x/crypto/sha3        7.299s
ok      golang.org/x/crypto/ssh 7.003s
ok      golang.org/x/crypto/ssh/agent   5.485s
ok      golang.org/x/crypto/ssh/internal/bcrypt_pbkdf5.551s
ok      golang.org/x/crypto/ssh/knownhosts      4.933s
ok      golang.org/x/crypto/ssh/test    7.203s
ok      golang.org/x/crypto/tea 5.262s
ok      golang.org/x/crypto/twofish     5.440s
ok      golang.org/x/crypto/x509roots/nss       5.443s
ok      golang.org/x/crypto/xtea        5.443s
ok      golang.org/x/crypto/xts 5.450s