From: Sergey Kandaurov <pluknet@nginx.com>
Date: Wed, 18 Mar 2026 12:39:37 +0000 (+0400)
Subject: Mail: fixed clearing s->passwd in auth http requests.
X-Git-Tag: release-1.29.7~2
X-Git-Url: http://www.kaiwu.me/postgresql/commit/static/gitweb.js?a=commitdiff_plain;h=9bc13718fe8a59a4538805516be7e141070c22d6;p=nginx.git

Mail: fixed clearing s->passwd in auth http requests.

Previously, it was not properly cleared retaining length as part of
authenticating with CRAM-MD5 and APOP methods that expect to receive
password in auth response.  This resulted in null pointer dereference
and worker process crash in subsequent auth attempts with CRAM-MD5.

Reported by Arkadi Vainbrand.
---

diff --git a/src/mail/ngx_mail_auth_http_module.c b/src/mail/ngx_mail_auth_http_module.c
index 4ca6d6e24..3e5095a2d 100644
--- a/src/mail/ngx_mail_auth_http_module.c
+++ b/src/mail/ngx_mail_auth_http_module.c
@@ -1328,7 +1328,7 @@ ngx_mail_auth_http_create_request(ngx_mail_session_t *s, ngx_pool_t *pool,
         b->last = ngx_cpymem(b->last, "Auth-Salt: ", sizeof("Auth-Salt: ") - 1);
         b->last = ngx_copy(b->last, s->salt.data, s->salt.len);
 
-        s->passwd.data = NULL;
+        ngx_str_null(&s->passwd);
     }
 
     b->last = ngx_cpymem(b->last, "Auth-Protocol: ",