UBUNTU-CVE-2026-42784

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Source

https://ubuntu.com/security/CVE-2026-42784

Import Source

https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42784.json

JSON Data

https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-42784

Upstream

CVE-2026-42784

Published

2026-09-16T17:17:00Z

Modified

2026-09-24T02:00:15Z

Severity

7.4 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N CVSS Calculator
Ubuntu - medium

Summary

[none]

Details

A flaw was found in sequoia-openpgp. The library incorrectly infers key flags for older certificates when a key flags subpacket is missing, leading to a discrepancy in how key capabilities are viewed. This key flag confusion allows an attacker to bypass the back-signature check. Consequently, an attacker can illegitimately bind an arbitrary subkey to their own certificate and forge signatures, completely compromising cryptographic integrity.

References

Affected packages

Ubuntu:22.04:LTS / rust-sequoia-openpgp

Package

Name: rust-sequoia-openpgp
Purl: pkg:deb/ubuntu/rust-sequoia-openpgp?arch=source&distro=jammy

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.1.0-3

1.3.0-4

1.7.0-6

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "librust-sequoia-openpgp+bzip2-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp+compression-bzip2-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp+compression-deflate-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp+compression-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp+default-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp+flate2-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp+nettle-dev",
            "binary_version":  "1.7.0-6"
        },
        {
            "binary_name":  "librust-sequoia-openpgp-dev",
            "binary_version":  "1.7.0-6"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42784.json"

Ubuntu:24.04:LTS / rust-sequoia-openpgp

Package

Name: rust-sequoia-openpgp
Purl: pkg:deb/ubuntu/rust-sequoia-openpgp?arch=source&distro=noble

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.16.0-1

1.17.0-1

1.17.0-2

1.18.0-1

1.19.0-1

1.19.0-1build1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "librust-sequoia-openpgp-dev",
            "binary_version":  "1.19.0-1build1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42784.json"

Ubuntu:25.10 / rust-sequoia-openpgp

Package

Name: rust-sequoia-openpgp
Purl: pkg:deb/ubuntu/rust-sequoia-openpgp?arch=source&distro=questing

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.22.0-1

2.*

2.0.0-2

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "librust-sequoia-openpgp-dev",
            "binary_version":  "2.0.0-2"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42784.json"

Ubuntu:26.04:LTS / rust-sequoia-openpgp

Package

Name: rust-sequoia-openpgp
Purl: pkg:deb/ubuntu/rust-sequoia-openpgp?arch=source&distro=resolute

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.0.0-2

2.0.0-5

2.1.0-1

2.1.0-2

2.1.0-3

2.2.0-1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "librust-sequoia-openpgp-dev",
            "binary_version":  "2.2.0-1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42784.json"