Request to Submit Bug for Encryption with ky1024_cv448 in GNUPG versions 2.5.9 - 2.5.11

Tanveer Salim via Gnupg-devel <[email protected]> Fri, 22 Aug 2025 04:56:54 +0200 (CEST)

Newsgroups	gmane.comp.encryption.gpg.devel
Message-ID	<[email protected]>

Hello!

I wish to subscribe the gnupg-devel mailing list to report a software

bug in GNUPG versions 2.5.9 - 2.5.11: Encryption with ky1024_cv448.

Attached is my GNUPG posteo (ed25519) public key so GNUPG

developers can verify PGP-signed emails sent by me henceforth.

I also attach the Kyber1024-Cv448-Ed448 PGP public key I used in this email

as well for signing verification.

Finally, I attach digital signatures of public keys so you can verify I own these

public keys.

Please let me know if I am allowed to join the mailing list.

Best,

Tanveer Salim 

_______________________________________________
Gnupg-devel mailing list
[email protected]
https://lists.gnupg.org/mailman/listinfo/gnupg-devel

gnupg_bug_ky1024_cv448_Encryption_Fails_GNUPG_2.5.9+.md (text/markdown, 6.1 KB)

Hello GNUPG Developers!

I was trying to send an GNUPG encrypted, signed email

to someone. I was unable to encrypt the email using

my ky1024_cv448 encryption key.

I am using GNU/Debian Linux.

Here is some info on my operating system:

```
[I] fosres@fosres ~> uname -a
Linux fosres 6.1.0-37-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.140-1 (2025-05-22) x86_64 GNU/Linux
```

I noticed when I use GNUPG versions 2.5.9 - 2.5.11 the encryption with

my subkey fails.

Below is information on my GPG public key:

```
[I] fosres@fosres ~> gpg --list-keys [email protected]
pub   ed448 2025-03-03 [SC]
      CBF3EECC5251C3C6A717F67EC350285589257AF7D44509BAFC63CC57729A07C4
uid           [ultimate] Tanveer Salim (This is the Official PGP Key to send and receive encrypted, signed emails to and from Tanveer Salim.) <[email protected]>
sub   ky1024_cv448 2025-03-03 [E]
      DBE82B00E56142EBAA46815CFA85CBFC3709130C1887105B951F7069484E08C9
```

When I use GNUPG versions <= 2.5.8 encryption with the ky1024_cv448

works.

When using GNUPG version 2.5.8 I am using libgcrypt 1.11.2:

```
[I] fosres@fosres ~> gpg --version
gpg (GnuPG) 2.5.8
libgcrypt 1.11.2
Copyright (C) 2025 g10 Code GmbH
License GNU GPL-3.0-or-later <https://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Home: /home/fosres/.gnupg
Supported algorithms:
Pubkey: RSA, Kyber, ELG, DSA, ECDH, ECDSA, EDDSA
Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH,
        CAMELLIA128, CAMELLIA192, CAMELLIA256
Hash: SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed
```

I tried encrypting the `test.txt` file attached in this email:

```
[I] fosres@fosres /tmp> cat /tmp/test.txt
Test
```

I was able to encrypt the file using the following command:

```
[I] fosres@fosres /tmp> gpg --armor -u [email protected] -r [email protected] --encrypt --sign /tmp/test.txt
File '/tmp/test.txt.asc' exists. Overwrite? (y/N) y
```

The resulting encryption file is the following:

```
[I] fosres@fosres /tmp> cat /tmp/test.txt.asc
-----BEGIN PGP MESSAGE-----
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=uFeI
-----END PGP MESSAGE-----
```

And the following is the result of decrypting the above Encrypted

Message:

```
[I] fosres@fosres /tmp> gpg --decrypt /tmp/test.txt.asc
gpg: encrypted with ky1024_cv448 key, ID DBE82B00E56142EB, created 2025-03-03
      "Tanveer Salim (This is the Official PGP Key to send and receive encrypted, signed emails to and from Tanveer Salim.) <[email protected]>"
Test
gpg: Signature made Sun 17 Aug 2025 09:37:50 PM CDT
gpg:                using EDDSA key CBF3EECC5251C3C6A717F67EC350285589257AF7D44509BAFC63CC57729A07C4
gpg:                issuer "[email protected]"
gpg: Good signature from "Tanveer Salim (This is the Official PGP Key to send and receive encrypted, signed emails to and from Tanveer Salim.) <[email protected]>" [ultimate]
```


When I upgrade to GNUPG versions 2.5.9 - 2.5.11 with libgrcypt version

1.11.2 I get the following error:

```
[I] fosres@fosres /tmp> gpg --armor -u [email protected] -r [email protected] --encrypt --sign /tmp/test.txt
gpg: pubkey_encrypt failed: Invalid length
gpg: filter_flush failed on close: Invalid length
```

Please let me know what the GNUPG developers think of this bug.

If I have configured anything incorrectly please let me know.

If this a true bug I am happy to cooperate to help test that the

GPG encryption works in 2.5.11 for ky1024_cv448 and other curves.

Best,

Tanveer Salim

gnupg_bug_ky1024_cv448_Encryption_Fails_GNUPG_2.5.9+.md.sig.asc (application/pgp-keys, 338 B)

ts.kyber1024_cv448.pub.asc (application/pgp-keys, 3.5 KB)

ts.kyber1024_cv448.sig.asc (application/pgp-keys, 338 B)