These two patches have already been merged in busybox repo.

Regards,
Qi

-----Original Message-----
From: [email protected] 
<[email protected]> On Behalf Of Hitendra Prajapati via 
lists.openembedded.org
Sent: Wednesday, March 18, 2026 8:24 PM
To: [email protected]
Cc: Hitendra Prajapati <[email protected]>
Subject: [OE-core] [scarthgap][PATCH] busybox: fix for CVE-2026-26157, 
CVE-2026-26158

Although the patch was not merged yet, Debian already took it ([1] & [2]).
Since busybox CVE handling is slow, follow Debian decision.

[1] 
https://sources.debian.org/src/busybox/1:1.37.0-10.1/debian/patches/0001-tar-strip-unsafe-hardlink-components-GNU-tar-does-th.patch
[2] 
https://sources.debian.org/src/busybox/1:1.37.0-10.1/debian/patches/0002-tar-only-strip-unsafe-components-from-hardlinks-not-.patch

Details:
1. https://nvd.nist.gov/vuln/detail/CVE-2026-26157
2. https://nvd.nist.gov/vuln/detail/CVE-2026-26158

Signed-off-by: Hitendra Prajapati <[email protected]>
---
 .../CVE-2026-26157-CVE-2026-26158-01.patch    | 197 ++++++++++++++++++
 .../CVE-2026-26157-CVE-2026-26158-02.patch    |  35 ++++
 meta/recipes-core/busybox/busybox_1.36.1.bb   |   2 +
 3 files changed, 234 insertions(+)
 create mode 100644 
meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-01.patch
 create mode 100644 
meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-02.patch

diff --git 
a/meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-01.patch 
b/meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-01.patch
new file mode 100644
index 0000000000..8649f4dfa5
--- /dev/null
+++ b/meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-01
+++ .patch
@@ -0,0 +1,197 @@
+From 0c20d6b353b058ab910dd3a0211e2b906802b105 Mon Sep 17 00:00:00 2001
+From: Denys Vlasenko <[email protected]>
+Date: Thu, 29 Jan 2026 11:48:02 +0100
+Subject: tar: strip unsafe hardlink components - GNU tar does the same
+
+Defends against files like these (python reproducer):
+
+import tarfile
+ti = tarfile.TarInfo("leak_hosts")
+ti.type = tarfile.LNKTYPE
+ti.linkname = "/etc/hosts"  # or "../etc/hosts" or ".."
+ti.size = 0
+with tarfile.open("/tmp/hardlink.tar", "w") as t:
+       t.addfile(ti)
+
+function                                             old     new   delta
+skip_unsafe_prefix                                     -     127    +127
+get_header_tar                                      1752    1754      +2
+.rodata                                           106861  106856      -5
+unzip_main                                          2715    2706      -9
+strip_unsafe_prefix                                  102      18     -84
+------------------------------------------------------------------------------
+(add/remove: 1/0 grow/shrink: 1/3 up/down: 129/-98)            Total: 31 bytes
+
+Signed-off-by: Denys Vlasenko <[email protected]>
+
+CVE: CVE-2026-26157, CVE-2026-26158
+Upstream-Status: Backport 
+[https://github.com/mirror/busybox/commit/3fb6b31c716669e12f75a2accd31b
+b7685b1a1cb]
+Signed-off-by: Hitendra Prajapati <[email protected]>
+---
+ archival/libarchive/data_extract_all.c      |  7 +++--
+ archival/libarchive/get_header_tar.c        | 11 ++++++--
+ archival/libarchive/unsafe_prefix.c         | 30 +++++++++++++++++----
+ archival/libarchive/unsafe_symlink_target.c |  1 +
+ archival/tar.c                              |  2 +-
+ archival/unzip.c                            |  2 +-
+ include/bb_archive.h                        |  3 ++-
+ 7 files changed, 42 insertions(+), 14 deletions(-)
+
+diff --git a/archival/libarchive/data_extract_all.c 
+b/archival/libarchive/data_extract_all.c
+index 8a69711..b84b960 100644
+--- a/archival/libarchive/data_extract_all.c
++++ b/archival/libarchive/data_extract_all.c
+@@ -66,8 +66,8 @@ void FAST_FUNC data_extract_all(archive_handle_t 
*archive_handle)
+       }
+ #endif
+ #if ENABLE_FEATURE_PATH_TRAVERSAL_PROTECTION
+-      /* Strip leading "/" and up to last "/../" path component */
+-      dst_name = (char *)strip_unsafe_prefix(dst_name);
++      /* Skip leading "/" and past last ".." path component */
++      dst_name = (char *)skip_unsafe_prefix(dst_name);
+ #endif
+ // ^^^ This may be a problem if some applets do need to extract absolute 
names.
+ // (Probably will need to invent ARCHIVE_ALLOW_UNSAFE_NAME flag).
+@@ -185,8 +185,7 @@ void FAST_FUNC data_extract_all(archive_handle_t 
+*archive_handle)
+ 
+               /* To avoid a directory traversal attack via symlinks,
+                * do not restore symlinks with ".." components
+-               * or symlinks starting with "/", unless a magic
+-               * envvar is set.
++               * or symlinks starting with "/"
+                *
+                * For example, consider a .tar created via:
+                *  $ tar cvf bug.tar anything.txt
+diff --git a/archival/libarchive/get_header_tar.c 
+b/archival/libarchive/get_header_tar.c
+index cc6f3f0..1c40ece 100644
+--- a/archival/libarchive/get_header_tar.c
++++ b/archival/libarchive/get_header_tar.c
+@@ -454,8 +454,15 @@ char FAST_FUNC get_header_tar(archive_handle_t 
+*archive_handle)  #endif
+ 
+       /* Everything up to and including last ".." component is stripped */
+-      overlapping_strcpy(file_header->name, 
strip_unsafe_prefix(file_header->name));
+-//TODO: do the same for file_header->link_target?
++      strip_unsafe_prefix(file_header->name);
++      if (file_header->link_target) {
++              /* GNU tar 1.34 examples:
++               * tar: Removing leading '/' from hard link targets
++               * tar: Removing leading '../' from hard link targets
++               * tar: Removing leading 'etc/../' from hard link targets
++               */
++              strip_unsafe_prefix(file_header->link_target);
++      }
+ 
+       /* Strip trailing '/' in directories */
+       /* Must be done after mode is set as '/' is used to check if it's a 
+directory */ diff --git a/archival/libarchive/unsafe_prefix.c 
+b/archival/libarchive/unsafe_prefix.c
+index 6670811..89a371a 100644
+--- a/archival/libarchive/unsafe_prefix.c
++++ b/archival/libarchive/unsafe_prefix.c
+@@ -5,11 +5,11 @@
+ #include "libbb.h"
+ #include "bb_archive.h"
+ 
+-const char* FAST_FUNC strip_unsafe_prefix(const char *str)
++const char* FAST_FUNC skip_unsafe_prefix(const char *str)
+ {
+       const char *cp = str;
+       while (1) {
+-              char *cp2;
++              const char *cp2;
+               if (*cp == '/') {
+                       cp++;
+                       continue;
+@@ -22,10 +22,25 @@ const char* FAST_FUNC strip_unsafe_prefix(const char *str)
+                       cp += 3;
+                       continue;
+               }
+-              cp2 = strstr(cp, "/../");
++              cp2 = cp;
++ find_dotdot:
++              cp2 = strstr(cp2, "/..");
+               if (!cp2)
+-                      break;
+-              cp = cp2 + 4;
++                      break; /* No (more) malicious components */
++
++              /* We found "/..something" */
++              cp2 += 3;
++              if (*cp2 != '/') {
++                      if (*cp2 == '\0') {
++                              /* Trailing "/..": malicious, return "" */
++                              /* (causes harmless errors trying to create or 
hardlink a file named "") */
++                              return cp2;
++                      }
++                      /* "/..name" is not malicious, look for next "/.." */
++                      goto find_dotdot;
++              }
++              /* Found "/../": malicious, advance past it */
++              cp = cp2 + 1;
+       }
+       if (cp != str) {
+               static smallint warned = 0;
+@@ -37,3 +52,8 @@ const char* FAST_FUNC strip_unsafe_prefix(const char *str)
+       }
+       return cp;
+ }
++
++void FAST_FUNC strip_unsafe_prefix(char *str) {
++      overlapping_strcpy(str, skip_unsafe_prefix(str)); }
+diff --git a/archival/libarchive/unsafe_symlink_target.c 
+b/archival/libarchive/unsafe_symlink_target.c
+index f8dc803..d764c89 100644
+--- a/archival/libarchive/unsafe_symlink_target.c
++++ b/archival/libarchive/unsafe_symlink_target.c
+@@ -36,6 +36,7 @@ void FAST_FUNC create_links_from_list(llist_t *list)
+                               *list->data ? "hard" : "sym",
+                               list->data + 1, target
+                       );
++                      /* Note: GNU tar 1.34 errors out only _after_ all links 
are 
++(attempted to be) created */
+               }
+               list = list->link;
+       }
+diff --git a/archival/tar.c b/archival/tar.c index 9de3759..cf8c2d1 
+100644
+--- a/archival/tar.c
++++ b/archival/tar.c
+@@ -475,7 +475,7 @@ static int FAST_FUNC writeFileToTarball(struct 
recursive_state *state,
+       DBG("writeFileToTarball('%s')", fileName);
+ 
+       /* Strip leading '/' and such (must be before memorizing hardlink's 
name) */
+-      header_name = strip_unsafe_prefix(fileName);
++      header_name = skip_unsafe_prefix(fileName);
+ 
+       if (header_name[0] == '\0')
+               return TRUE;
+diff --git a/archival/unzip.c b/archival/unzip.c index 691a2d8..5844215 
+100644
+--- a/archival/unzip.c
++++ b/archival/unzip.c
+@@ -853,7 +853,7 @@ int unzip_main(int argc, char **argv)
+               unzip_skip(zip.fmt.extra_len);
+ 
+               /* Guard against "/abspath", "/../" and similar attacks */
+-              overlapping_strcpy(dst_fn, strip_unsafe_prefix(dst_fn));
++              strip_unsafe_prefix(dst_fn);
+ 
+               /* Filter zip entries */
+               if (find_list_entry(zreject, dst_fn) diff --git 
+a/include/bb_archive.h b/include/bb_archive.h index e0ef8fc..1dc77f3 
+100644
+--- a/include/bb_archive.h
++++ b/include/bb_archive.h
+@@ -202,7 +202,8 @@ char get_header_tar_xz(archive_handle_t 
+*archive_handle) FAST_FUNC;  void seek_by_jump(int fd, off_t amount) 
+FAST_FUNC;  void seek_by_read(int fd, off_t amount) FAST_FUNC;
+ 
+-const char *strip_unsafe_prefix(const char *str) FAST_FUNC;
++const char *skip_unsafe_prefix(const char *str) FAST_FUNC; void 
++strip_unsafe_prefix(char *str) FAST_FUNC;
+ void create_or_remember_link(llist_t **link_placeholders,
+               const char *target,
+               const char *linkname,
+--
+2.50.1
+
diff --git 
a/meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-02.patch 
b/meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-02.patch
new file mode 100644
index 0000000000..1380a6f72e
--- /dev/null
+++ b/meta/recipes-core/busybox/busybox/CVE-2026-26157-CVE-2026-26158-02
+++ .patch
@@ -0,0 +1,35 @@
+From 038e0e4d791ea4e8a8da5e06904756142fc6b8dc Mon Sep 17 00:00:00 2001
+From: Radoslav Kolev <[email protected]>
+Date: Mon, 16 Feb 2026 11:50:04 +0200
+Subject: tar: only strip unsafe components from hardlinks, not symlinks
+
+commit 3fb6b31c7 introduced a check for unsafe components in tar 
+archive hardlinks, but it was being applied to symlinks too which broke 
+"Symlinks and hardlinks coexist" tar test.
+
+Signed-off-by: Radoslav Kolev <[email protected]>
+Signed-off-by: Denys Vlasenko <[email protected]>
+
+CVE: CVE-2026-26157, CVE-2026-26158
+Upstream-Status: Backport 
+[https://github.com/mirror/busybox/commit/3fb6b31c716669e12f75a2accd31b
+b7685b1a1cb]
+Signed-off-by: Hitendra Prajapati <[email protected]>
+---
+ archival/libarchive/get_header_tar.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/archival/libarchive/get_header_tar.c 
+b/archival/libarchive/get_header_tar.c
+index 1c40ece..606d806 100644
+--- a/archival/libarchive/get_header_tar.c
++++ b/archival/libarchive/get_header_tar.c
+@@ -455,7 +455,7 @@ char FAST_FUNC get_header_tar(archive_handle_t 
+*archive_handle)
+ 
+       /* Everything up to and including last ".." component is stripped */
+       strip_unsafe_prefix(file_header->name);
+-      if (file_header->link_target) {
++      if (file_header->link_target && !S_ISLNK(file_header->mode)) {
+               /* GNU tar 1.34 examples:
+                * tar: Removing leading '/' from hard link targets
+                * tar: Removing leading '../' from hard link targets
+--
+2.50.1
+
diff --git a/meta/recipes-core/busybox/busybox_1.36.1.bb 
b/meta/recipes-core/busybox/busybox_1.36.1.bb
index d870e2ee10..228bfdadd3 100644
--- a/meta/recipes-core/busybox/busybox_1.36.1.bb
+++ b/meta/recipes-core/busybox/busybox_1.36.1.bb
@@ -62,6 +62,8 @@ SRC_URI = 
"https://busybox.net/downloads/busybox-${PV}.tar.bz2;name=tarball \
            file://CVE-2025-46394-01.patch \
            file://CVE-2025-46394-02.patch \
            file://CVE-2025-60876.patch \
+           file://CVE-2026-26157-CVE-2026-26158-01.patch \
+           file://CVE-2026-26157-CVE-2026-26158-02.patch \
            "
 SRC_URI:append:libc-musl = " file://musl.cfg "
 # TODO http://lists.busybox.net/pipermail/busybox/2023-January/090078.html
--
2.50.1

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