new file mode 100644
@@ -0,0 +1,155 @@
+From a448b6d5b21e5b21249391389b6f0551d9bea136 Mon Sep 17 00:00:00 2001
+From: Sanghyun Park <sanghyun.park.cnu@gmail.com>
+Date: Thu, 18 Jun 2026 17:04:20 +0900
+Subject: [PATCH] ash: fix out-of-bounds read in ifsbreakup()
+
+ifsfree() does not only release allocated ifsregion nodes; it also clears
+the global IFS region state used by ifsbreakup(). If argstr() raises an
+error while expanding an argument, ash longjmps out of expandarg() before
+that cleanup runs, leaving stale IFS split offsets behind.
+
+A later expansion can reuse the stack for a shorter string. ifsbreakup()
+then sees the stale IFS state, trusts the old offsets, and can walk past
+the current stack block before dereferencing p.
+
+Follow dash's root-cause fix: when an expansion-related handler catches
+EXERROR and continues, restore the handler and call ifsfree(). Apply
+the cleanup to redirectsafe(), expandstr(), and evaltree().
+
+Upstream commit:
+
+ Date: Mon Dec 5 23:02:01 2022 +0800
+ expand: Add ifsfree to expand to fix a logic error that causes a buffer over-read
+
+ On Mon, Jun 20, 2022 at 02:27:10PM -0400, Alex Gorinson wrote:
+ > Due to a logic error in the ifsbreakup function in expand.c if a
+ > heredoc and normal command is run one after the other by means of a
+ > semi-colon, when the second command drops into ifsbreakup the command
+ > will be evaluated with the ifslastp/ifsfirst struct that was set when
+ > the here doc was evaluated. This results in a buffer over-read that
+ > can leak the program's heap, stack, and arena addresses which can be
+ > used to beat ASLR.
+ >
+ > Steps to Reproduce:
+ > First bug:
+ > cmd args: ~/exampleDir/example> dash
+ > $ M='AAAAAAAAAAAAAAAAA' <note: 17 A's>
+ > $ q00(){
+ > $ <<000;echo
+ > $ ${D?$M$M$M$M$M$M} <note: 6 $M's>
+ > $ 000
+ > $ }
+ > $ q00 <note: After the q00 is typed in, the leak
+ > should be echo'd out; this works with ash, busybox ash, and dash and
+ > with all option args.>
+ >
+ > Patch:
+ > Adding the following to expand.c will fix both bugs in one go.
+ > (Thank you to Harald van Dijk and Michael Greenberg for doing the
+ > heavy lifting for this patch!)
+ > ==========================
+ > --- a/src/expand.c
+ > +++ b/src/expand.c
+ > @@ -859,6 +859,7 @@
+ > if (discard)
+ > return -1;
+ >
+ > +ifsfree();
+ > sh_error("Bad substitution");
+ > }
+ >
+ > @@ -1739,6 +1740,7 @@
+ > } else
+ > msg = umsg;
+ > }
+ > +ifsfree();
+ > sh_error("%.*s: %s%s", end - var - 1, var, msg, tail);
+ > }
+ > ==========================
+
+ Thanks for the report!
+
+ I think it's better to add the ifsfree() call to the exception
+ handling path as other sh_error calls may trigger this too.
+
+function old new delta
+restore_handler_expandarg - 33 +33
+evaltree 725 711 -14
+static.redirectsafe 141 124 -17
+expandstr 262 242 -20
+------------------------------------------------------------------------------
+(add/remove: 1/0 grow/shrink: 0/3 up/down: 36/-45) Total: -18 bytes
+
+Signed-off-by: Sanghyun Park <sanghyun.park.cnu@gmail.com>
+Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
+
+CVE: CVE-2026-38754
+Upstream-Status: Backport [https://github.com/vda-linux/busybox_mirror/commit/a448b6d5b21e5b21249391389b6f0551d9bea136]
+Signed-off-by: Peter Marko <peter.marko@siemens.com>
+---
+ shell/ash.c | 24 +++++++++++++++---------
+ 1 file changed, 15 insertions(+), 9 deletions(-)
+
+diff --git a/shell/ash.c b/shell/ash.c
+index fb887f31b..b8ff67b16 100644
+--- a/shell/ash.c
++++ b/shell/ash.c
+@@ -5480,6 +5480,7 @@ stoppedjobs(void)
+ */
+ /* openhere needs this forward reference */
+ static void expandhere(union node *arg);
++static void ifsfree(void);
+ static int
+ openhere(union node *redir)
+ {
+@@ -5909,6 +5910,17 @@ redirect(union node *redir, int flags)
+ // preverrout_fd = copied_fd2;
+ }
+
++static void
++restore_handler_expandarg(struct jmploc *savehandler, int err)
++{
++ exception_handler = savehandler;
++ if (err) {
++ if (exception_type != EXERROR)
++ longjmp(exception_handler->loc, 1);
++ ifsfree();
++ }
++}
++
+ static int
+ redirectsafe(union node *redir, int flags)
+ {
+@@ -5924,9 +5936,7 @@ redirectsafe(union node *redir, int flags)
+ exception_handler = &jmploc;
+ redirect(redir, flags);
+ }
+- exception_handler = savehandler;
+- if (err && exception_type != EXERROR)
+- longjmp(exception_handler->loc, 1);
++ restore_handler_expandarg(savehandler, err);
+ RESTORE_INT(saveint);
+ return err;
+ }
+@@ -9435,9 +9445,7 @@ evaltree(union node *n, int flags)
+ trap_depth--;
+ in_trap_ERR = 0;
+
+- exception_handler = savehandler;
+- if (err && exception_type != EXERROR)
+- longjmp(exception_handler->loc, 1);
++ restore_handler_expandarg(savehandler, err);
+
+ exitstatus = savestatus;
+ }
+@@ -13444,9 +13452,7 @@ expandstr(const char *ps, int syntax_type)
+ result = stackblock();
+
+ out:
+- exception_handler = savehandler;
+- if (err && exception_type != EXERROR)
+- longjmp(exception_handler->loc, 1);
++ restore_handler_expandarg(savehandler, err);
+
+ doprompt = saveprompt;
+ /* Try: PS1='`xxx(`' */
@@ -66,6 +66,7 @@ SRC_URI = "https://busybox.net/downloads/busybox-${PV}.tar.bz2;name=tarball \
file://CVE-2026-26157-CVE-2026-26158-02.patch \
file://CVE-2026-29004-01.patch \
file://CVE-2026-29004-02.patch \
+ file://CVE-2026-38754.patch \
"
SRC_URI:append:libc-musl = " file://musl.cfg "
# TODO http://lists.busybox.net/pipermail/busybox/2023-January/090078.html