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.
Metrics
Affected Vendors & Products
No data.
No data.
OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.
| Vendors | Products |
|---|---|
|
Perl
Subscribe
|
Authen::sasl::perl::digest Md5
Subscribe
|
No advisories yet.
Solution
Upgrade to Authen-SASL 2.2100 or later.
Workaround
No workaround given by the vendor.
Mon, 07 Sep 2026 08:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Perl
Perl authen::sasl::perl::digest Md5 |
|
| Vendors & Products |
Perl
Perl authen::sasl::perl::digest Md5 |
Sun, 06 Sep 2026 18:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step | |
| Weaknesses | CWE-294 | |
| References |
|
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: CPANSec
Published:
Updated: 2026-09-06T17:46:30.340Z
Reserved: 2026-09-06T00:13:35.358Z
Link: CVE-2026-86219
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-06T18:17:23.027
Modified: 2026-09-06T18:17:23.027
Link: CVE-2026-86219
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-09-07T08:24:32Z