Bug 920293

Summary:	net-misc/dropbear: terrapin vulnerability
Product:	Gentoo Security	Reporter:	Christopher Fore <csfore>
Component:	Vulnerabilities	Assignee:	Gentoo Security <security>
Status:	CONFIRMED ---
Severity:	normal	CC:	embedded
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	https://terrapin-attack.com/
Whiteboard:	A3 [stable?]
Package list:		Runtime testing required:	---
Bug Depends on:
Bug Blocks:	920280

Description Christopher Fore 2023-12-18 23:46:22 UTC

CVE-2023-48795 (https://terrapin-attack.com/):

The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and mishandles use of sequence numbers. For example, there is an effective attack against ChaCha20-Poly1305 (and CBC with Encrypt-then-MAC). The bypass occurs in chacha20-poly1305@openssh.com and (if CBC is used) the -etm@openssh.com MAC algorithms. This also affects Maverick Synergy Java SSH API before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, and PuTTY before 0.80; and there could be effects on Bitvise SSH through 9.31, AsyncSSH through 2.14.1, libssh through 0.10.5, and golang.org/x/crypto through 2023-12-17.

Comment 1 Larry the Git Cow gentoo-dev

2024-04-06 05:58:16 UTC

The bug has been referenced in the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=ca104be35e918af32f622d4f2e0850085e36da63

commit ca104be35e918af32f622d4f2e0850085e36da63
Author:     Viorel Munteanu <ceamac@gentoo.org>
AuthorDate: 2024-04-06 05:52:39 +0000
Commit:     Viorel Munteanu <ceamac@gentoo.org>
CommitDate: 2024-04-06 05:54:50 +0000

    net-misc/dropbear: add 2024.84
    
    Make the tests non-interactive just in case.
    Disable the tests that fail.
    
    Closes: https://bugs.gentoo.org/732294
    Bug: https://bugs.gentoo.org/920293
    Signed-off-by: Viorel Munteanu <ceamac@gentoo.org>

 net-misc/dropbear/Manifest                         |   2 +
 net-misc/dropbear/dropbear-2024.84.ebuild          | 184 +++++++++++++++++++++
 .../dropbear/files/dropbear-2024.84-dbscp.patch    |  20 +++
 .../dropbear-2024.84-non-interactive-tests.patch   |  13 ++
 4 files changed, 219 insertions(+)