CVE-2026-86219

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.

Authen::SASL::Perl is the pure Perl implementation of SASL mechanisms in the Authen::SASL framework, At the time of this writing it provides the client part implementation for the following SASL mechanisms.

Security Fix(es):

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.(CVE-2026-86219)

Authen::SASL::Perl is the pure Perl implementation of SASL mechanisms in the Authen::SASL framework, At the time of this writing it provides the client part implementation for the following SASL mechanisms.

Security Fix(es):

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.(CVE-2026-86219)

Authen::SASL::Perl is the pure Perl implementation of SASL mechanisms in the Authen::SASL framework, At the time of this writing it provides the client part implementation for the following SASL mechanisms.

Security Fix(es):

Authen::SASL::Perl::DIGEST_MD5 versions 2.04 through 2.1800 for Perl generates the cnonce insecurely. The cnonce (client nonce) is generated from an MD5 hash of the PID, the epoch time and the built-in rand function. The PID comes from a small set of numbers, and the epoch time may be guessed if not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage. According to RFC 2831, the cnonce-value should be provided by the client and contain at least 64 bits of entropy to ensure security.(CVE-2025-40918)

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.(CVE-2026-86219)

Authen::SASL::Perl is the pure Perl implementation of SASL mechanisms in the Authen::SASL framework, At the time of this writing it provides the client part implementation for the following SASL mechanisms.

Security Fix(es):

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.(CVE-2026-86219)

Authen::SASL::Perl is the pure Perl implementation of SASL mechanisms in the Authen::SASL framework, At the time of this writing it provides the client part implementation for the following SASL mechanisms.

Security Fix(es):

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step.

server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge.

An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.(CVE-2026-86219)

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying nc=00000001, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful qop=auth exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.

Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. (CVE-2026-86219)

These are all security issues fixed in the perl-Authen-SASL-2.210.0-1.1 package on the GA media of openSUSE Tumbleweed.

This update for perl-Authen-SASL fixes the following issue:

• CVE-2026-86219: replayed authentication responses accepted due to unverified nonce in server_step (bsc#1279806).

Root has patched CVE-2026-86219 in the libauthen-sasl-perl package for Root:Debian:12. Multiple fixed versions available.

This update for perl-Authen-SASL fixes the following issue:

• CVE-2026-86219: replayed authentication responses accepted due to unverified nonce in server_step (bsc#1279806).

This update for perl-Authen-SASL fixes the following issue:

• CVE-2026-86219: replayed authentication responses accepted due to unverified nonce in server_step (bsc#1279806).

This update for perl-Authen-SASL fixes the following issue:

• CVE-2026-86219: replayed authentication responses accepted due to unverified nonce in server_step (bsc#1279806).

It was discovered that Authen::SASL, a Perl authentication library, did not properly validate login attempts. An attacker could possibly use this issue to gain unauthorized access.