CVE-2026-50722

Name
CVE-2026-50722
Description
Libreswan, via the function RSA_authenticate_hash_signature_pkcs1_1_5_rsa(), did not correctly verify the DER encoding of the ASN.1 digest when the IKEv2 AUTH payload was encoded using RSASSA-PKCS1-v1_5 (RFC 8017). A remote attacker can use a variation on the Bleichenbacher attack to forge the AUTH payload when small public exponents are used (e.g., e=3), leading to impersonation. Additionally, a remote attacker, by encoding a shorter than expected hash in the AUTH payload, could trigger an assertion leading to denial-of-service. The daemon aborts and restarts; continued exploitation causes sustained denial of service. Remote code execution is not possible. X.509 certificate verifications of the remote IKE peer are not affected.
NVD Severity
unknown
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
d42dc95b-23f1-4e06-9076-20753a0fb0df https://libreswan.org/security/CVE-2026-50721/CVE-2026-50721.txt
d42dc95b-23f1-4e06-9076-20753a0fb0df https://libreswan.org/security/CVE-2026-50722/
d42dc95b-23f1-4e06-9076-20753a0fb0df https://libreswan.org/security/CVE-2026-50722/CVE-2026-50722.txt
d42dc95b-23f1-4e06-9076-20753a0fb0df https://www.rfc-editor.org/rfc/rfc8017

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:libreswan:libreswan:*:*:*:*:*:*:*:* libreswan >= None < 5.3.1

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
libreswan edge-community 5.3.1-r0 Natanael Copa <ncopa@alpinelinux.org> fixed
libreswan edge-community 5.3-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 5.2-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 5.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 5.0-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 4.15-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 4.12-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 4.6-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libreswan edge-community 3.32-r0 None possibly vulnerable
libreswan edge-community 3.29-r0 None possibly vulnerable
libreswan edge-community 3.28-r0 None possibly vulnerable
libreswan 3.24-community 5.3-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable