[Pkg-rust-maintainers] Bug#1122582: sequoia-openpgp: DOS (crahsh) via special crafted encrypted message

[Holger Levsen]

Package: rust-sequoia-openpgp
Version: 1.1.0-3
Severity: important
Tags: security

https://gitlab.com/sequoia-pgp/sequoia/-/commit/b59886e5e7bdf7169ed330f309a6633d131776e5
which was first released with rust-sequoia-openpgp 2.1.0
describes (and then fixes) the following problem:

openpgp: Fix an underflow in aes_key_unwrap.

The `aes_key_unwrap` function would panic if passed a ciphertext
that was too short.  In a debug build, it would panic due to a
subtraction underflow.  In a release build, it would use the small
negative quantity to allocate a vector.  Since the allocator
expects an unsigned quantity, the negative value would be
interpreted as a huge allocation.  The allocator would then fail
to allocate the memory and panic.

An attacker could trigger this panic by sending a victim an
encrypted message whose PKESK or SKESK packet has been specially
modified.  When the victim decrypts the message, the program would
crash.

Reported-by: Jan Różański.


-- 
cheers,
	Holger

 ⢀⣴⠾⠻⢶⣦⠀
 ⣾⠁⢠⠒⠀⣿⡁  holger@(debian|reproducible-builds|layer-acht).org
 ⢿⡄⠘⠷⠚⠋⠀  OpenPGP: B8BF54137B09D35CF026FE9D 091AB856069AAA1C
 ⠈⠳⣄

Ich glaube die Letzte Generation ist die erste kriminelle Vereinigung in der
Geschichte, deren einziges Ziel es ist, dass sich die Regierung an die
Verfassung und ihre eigenen Gesetze hält. (@muellermusik)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://alioth-lists.debian.net/pipermail/pkg-rust-maintainers/attachments/20251211/5ead2d6e/attachment.sig>