CVE-2019-11841
Publication date 22 May 2019
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
A message-forgery issue was discovered in crypto/openpgp/clearsign/clearsign.go in supplementary Go cryptography libraries 2019-03-25. According to the OpenPGP Message Format specification in RFC 4880 chapter 7, a cleartext signed message can contain one or more optional "Hash" Armor Headers. The "Hash" Armor Header specifies the message digest algorithm(s) used for the signature. However, the Go clearsign package ignores the value of this header, which allows an attacker to spoof it. Consequently, an attacker can lead a victim to believe the signature was generated using a different message digest algorithm than what was actually used. Moreover, since the library skips Armor Header parsing in general, an attacker can not only embed arbitrary Armor Headers, but also prepend arbitrary text to cleartext messages without invalidating the signatures.
Status
Package | Ubuntu Release | Status |
---|---|---|
golang-go.crypto | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Not affected
|
|
20.04 LTS focal |
Not affected
|
|
18.04 LTS bionic |
Vulnerable
|
|
16.04 LTS xenial |
Vulnerable
|
|
14.04 LTS trusty | Not in release | |
snapd | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Not affected
|
|
20.04 LTS focal |
Not affected
|
|
18.04 LTS bionic |
Not affected
|
|
16.04 LTS xenial |
Not affected
|
|
14.04 LTS trusty | Not in release |
Notes
jdstrand
snapd contains an embedded copy of golang-go.crypto the version of golang-go.crypto that is embedded does not contain the clearsign package. Nothing in the source uses the clearsign APIs
Patch details
Package | Patch details |
---|---|
golang-go.crypto |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 5.9 · Medium |
Attack vector | Network |
Attack complexity | High |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | High |
Availability impact | None |
Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N |