From ed51539d6e4a9d85a7ac35abd5a9f8802187d0bf Mon Sep 17 00:00:00 2001 From: Hetvi Thakar Date: Thu, 15 Oct 2026 20:20:50 -0700 Subject: [PATCH] nginx: fix CVE-2026-9256 This patch applies the upstream fix as referenced in [2], using the commit shown in [1]. [1] https://github.com/nginx/nginx/commit/3f135ae2eb60ce376196c898a6c7cb4d774f7068 [2] https://nginx.org/en/security_advisories.html Signed-off-by: Hetvi Thakar Signed-off-by: Anuj Mittal --- .../nginx/files/CVE-2026-9256.patch | 77 +++++++++++++++++++ .../recipes-httpd/nginx/nginx_1.28.3.bb | 1 + .../recipes-httpd/nginx/nginx_1.29.7.bb | 1 + 3 files changed, 79 insertions(+) create mode 100644 meta-webserver/recipes-httpd/nginx/files/CVE-2026-9256.patch diff --git a/meta-webserver/recipes-httpd/nginx/files/CVE-2026-9256.patch b/meta-webserver/recipes-httpd/nginx/files/CVE-2026-9256.patch new file mode 100644 index 0000000000..7ffa188abf --- /dev/null +++ b/meta-webserver/recipes-httpd/nginx/files/CVE-2026-9256.patch @@ -0,0 +1,77 @@ +From 3f135ae2eb60ce376196c898a6c7cb4d774f7068 Mon Sep 17 00:00:00 2001 +From: Roman Arutyunyan +Date: Thu, 14 May 2026 18:42:18 +0400 +Subject: [PATCH] Rewrite: fix buffer overflow with overlapping captures + +When the rewrite replacement string had no variables, but had +overlapping captures, the length of the allocated buffer could be +smaller than the replacement string. This could happen either +when the "redirect" parameter is specified, or when arguments are +present in the replacement string. + +The following configurations resulted in heap buffer overflow when +using URI "/++++++++++++++++++++++++++++++": + + location / { + rewrite ^/((.*))$ http://127.0.0.1:8080/$1$2 redirect; + return 200 foo; + } + + location / { + rewrite ^/((.*))$ http://127.0.0.1:8080/?$1$2; + return 200 foo; + } + +Reported by Mufeed VH of Winfunc Research. + +CVE: CVE-2026-9256 +Upstream-Status: Backport [https://github.com/nginx/nginx/commit/3f135ae2eb60ce376196c898a6c7cb4d774f7068] + +(cherry picked from commit 3f135ae2eb60ce376196c898a6c7cb4d774f7068) +Signed-off-by: Hetvi Thakar +--- + src/http/ngx_http_script.c | 20 +++++++++++++------- + 1 file changed, 13 insertions(+), 7 deletions(-) + +diff --git a/src/http/ngx_http_script.c b/src/http/ngx_http_script.c +index 2ea611373..8a28e23a6 100644 +--- a/src/http/ngx_http_script.c ++++ b/src/http/ngx_http_script.c +@@ -1037,6 +1037,8 @@ ngx_http_script_start_args_code(ngx_http_script_engine_t *e) + void + ngx_http_script_regex_start_code(ngx_http_script_engine_t *e) + { ++ int *cap; ++ u_char *p; + size_t len; + ngx_int_t rc; + ngx_uint_t n; +@@ -1143,15 +1145,19 @@ ngx_http_script_regex_start_code(ngx_http_script_engine_t *e) + if (code->lengths == NULL) { + e->buf.len = code->size; + +- if (code->uri) { +- if (r->ncaptures && (r->quoted_uri || r->plus_in_uri)) { +- e->buf.len += 2 * ngx_escape_uri(NULL, r->uri.data, r->uri.len, +- NGX_ESCAPE_ARGS); +- } +- } ++ cap = r->captures; ++ p = r->captures_data; + + for (n = 2; n < r->ncaptures; n += 2) { +- e->buf.len += r->captures[n + 1] - r->captures[n]; ++ e->buf.len += cap[n + 1] - cap[n]; ++ ++ if (code->uri) { ++ if (r->quoted_uri || r->plus_in_uri) { ++ e->buf.len += 2 * ngx_escape_uri(NULL, &p[cap[n]], ++ cap[n + 1] - cap[n], ++ NGX_ESCAPE_ARGS); ++ } ++ } + } + + } else { +-- +2.35.6 diff --git a/meta-webserver/recipes-httpd/nginx/nginx_1.28.3.bb b/meta-webserver/recipes-httpd/nginx/nginx_1.28.3.bb index 308edd96bd..94ca40e36f 100644 --- a/meta-webserver/recipes-httpd/nginx/nginx_1.28.3.bb +++ b/meta-webserver/recipes-httpd/nginx/nginx_1.28.3.bb @@ -6,6 +6,7 @@ SRC_URI:append = " \ file://CVE-2026-42946_p1.patch \ file://CVE-2026-42946_p2.patch \ file://CVE-2026-42945.patch \ + file://CVE-2026-9256.patch \ " LIC_FILES_CHKSUM = "file://LICENSE;md5=3dc49537b08b14c8b66ad247bb4c4593" diff --git a/meta-webserver/recipes-httpd/nginx/nginx_1.29.7.bb b/meta-webserver/recipes-httpd/nginx/nginx_1.29.7.bb index 4a3d524346..c5f8ea2645 100644 --- a/meta-webserver/recipes-httpd/nginx/nginx_1.29.7.bb +++ b/meta-webserver/recipes-httpd/nginx/nginx_1.29.7.bb @@ -6,6 +6,7 @@ SRC_URI:append = " \ file://CVE-2026-42946_p1.patch \ file://CVE-2026-42946_p2.patch \ file://CVE-2026-42945.patch \ + file://CVE-2026-9256.patch \ " # 1.28.x branch is the current stable branch, the recommended default