PublicDateAtUSN: 2021-04-05 22:15:00 UTC
Candidate: CVE-2021-20305
PublicDate: 2021-04-05 22:15:00 UTC
References:
 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20305
 https://lists.lysator.liu.se/pipermail/nettle-bugs/2021/009457.html
 https://ubuntu.com/security/notices/USN-4906-1
Description:
 A flaw was found in Nettle in versions before 3.7.2, where several Nettle
 signature verification functions (GOST DSA, EDDSA & ECDSA) result in the
 Elliptic Curve Cryptography point (ECC) multiply function being called with
 out-of-range scalers, possibly resulting in incorrect results. This flaw
 allows an attacker to force an invalid signature, causing an assertion
 failure or possible validation. The highest threat to this vulnerability is
 to confidentiality, integrity, as well as system availability.
Ubuntu-Description:
Notes:
Mitigation:
Bugs:
 http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=985652
Priority: medium
Discovered-by:
Assigned-to: mdeslaur
CVSS:
 nvd: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H [8.1 HIGH]


Patches_nettle:
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/a63893791280d441c713293491da97c79c0950fe
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/971bed6ab4b27014eb23085e8176917e1a096fd5
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/74ee0e82b6891e090f20723750faeb19064e31b2
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/51f643eee00e2caa65c8a2f5857f49acdf3ef1ce
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/401c8d53d8a8cf1e79980e62bda3f946f8e07c14
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/ae3801a0e5cce276c270973214385c86048d5f7b
 upstream: https://git.lysator.liu.se/nettle/nettle/-/commit/63f222c60b03470c0005aa9bc4296fbf585f68b9
upstream_nettle: released (3.7.2-1)
precise/esm_nettle: DNE
trusty_nettle: ignored (out of standard support)
trusty/esm_nettle: needs-triage
xenial_nettle: released (3.2-1ubuntu0.16.04.2)
esm-infra/xenial_nettle: released (3.2-1ubuntu0.16.04.2)
bionic_nettle: released (3.4-1ubuntu0.1)
focal_nettle: released (3.5.1+really3.5.1-2ubuntu0.1)
groovy_nettle: released (3.6-2ubuntu0.1)
hirsute_nettle: released (3.7-2.1ubuntu1)
impish_nettle: released (3.7-2.1ubuntu1)
jammy_nettle: released (3.7-2.1ubuntu1)
devel_nettle: released (3.7-2.1ubuntu1)