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.

The remote Debian 10 host has a package installed that is affected by multiple vulnerabilities as referenced in the dla-3455 advisory.

  - An issue was discovered in supplementary Go cryptography libraries, aka golang-googlecode-go-crypto,     before 2019-03-20. A flaw was found in the amd64 implementation of golang.org/x/crypto/salsa20 and     golang.org/x/crypto/salsa20/salsa. If more than 256 GiB of keystream is generated, or if the counter     otherwise grows greater than 32 bits, the amd64 implementation will first generate incorrect output, and     then cycle back to previously generated keystream. Repeated keystream bytes can lead to loss of     confidentiality in encryption applications, or to predictability in CSPRNG applications. (CVE-2019-11840)

  - 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. (CVE-2019-11841)

  - golang.org/x/crypto before v0.0.0-20200220183623-bac4c82f6975 for Go allows a panic during signature     verification in the golang.org/x/crypto/ssh package. A client can attack an SSH server that accepts public     keys. Also, a server can attack any SSH client. (CVE-2020-9283)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

CVE-2019-11840

An issue was discovered in supplementary Go cryptography libraries, aka golang-googlecode-go-crypto. If more than 256 GiB of keystream is generated, or if the counter otherwise grows greater than 32 bits, the amd64 implementation will first generate incorrect output, and then cycle back to previously generated keystream. Repeated keystream bytes can lead to loss of confidentiality in encryption applications, or to predictability in CSPRNG applications.

CVE-2019-11841

A message-forgery issue was discovered in crypto/openpgp/clearsign/clearsign.go in supplementary Go cryptography libraries. The 'Hash' Armor Header specifies the message digest algorithm(s) used for the signature. 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.

CVE-2020-9283

golang.org/x/crypto allows a panic during signature verification in the golang.org/x/crypto/ssh package. A client can attack an SSH server that accepts public keys. Also, a server can attack any SSH client.

For Debian 9 stretch, these problems have been fixed in version 1:0.0~git20170407.0.55a552f+REALLY.0.0~git20161012.0.5f31782-1+deb8u1.

We recommend that you upgrade your golang-go.crypto packages.

For the detailed security status of golang-go.crypto please refer to its security tracker page at:
https://security-tracker.debian.org/tracker/golang-go.crypto

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

This package ignored the value of the Hash header, which allows an attacker to spoof it. An attacker can not only embed arbitrary Armor Headers, but also prepend arbitrary text to cleartext messages without invalidating the signatures.

For Debian 8 'Jessie', this problem has been fixed in version 0.0~hg190-1+deb8u2.

We recommend that you upgrade your golang-go.crypto packages.

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

ID	Name	Product	Family	Severity
177400	Debian DLA-3455-1 : golang-go.crypto - LTS security update	Nessus	Debian Local Security Checks	medium
141271	Debian DLA-2402-1 : golang-go.crypto security update	Nessus	Debian Local Security Checks	medium
128780	Debian DLA-1920-1 : golang-go.crypto security update	Nessus	Debian Local Security Checks	medium

Detections

Analytics

CVE-2019-11841

medium

Tenable Plugins

medium

medium

medium