python3.11/00482-cve-2026-6100.patch
Charalampos Stratakis 91083a10c7 Security fixes for CVE-2026-4786, CVE-2026-6100
Resolves: RHEL-168129, RHEL-167891
2026-04-17 04:06:57 +02:00

49 lines
1.8 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Stan Ulbrych <stan@python.org>
Date: Mon, 13 Apr 2026 22:42:36 +0100
Subject: 00482: CVE-2026-6100
Fix a possible UAF in {LZMA,BZ2,_Zlib}Decompressor
---
.../Security/2026-04-10-16-28-21.gh-issue-148395.kfzm0G.rst | 5 +++++
Modules/_bz2module.c | 1 +
Modules/_lzmamodule.c | 1 +
3 files changed, 7 insertions(+)
create mode 100644 Misc/NEWS.d/next/Security/2026-04-10-16-28-21.gh-issue-148395.kfzm0G.rst
diff --git a/Misc/NEWS.d/next/Security/2026-04-10-16-28-21.gh-issue-148395.kfzm0G.rst b/Misc/NEWS.d/next/Security/2026-04-10-16-28-21.gh-issue-148395.kfzm0G.rst
new file mode 100644
index 0000000000..349d1cf3ca
--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2026-04-10-16-28-21.gh-issue-148395.kfzm0G.rst
@@ -0,0 +1,5 @@
+Fix a dangling input pointer in :class:`lzma.LZMADecompressor`,
+and :class:`bz2.BZ2Decompressor`
+when memory allocation fails with :exc:`MemoryError`, which could let a
+subsequent :meth:`!decompress` call read or write through a stale pointer to
+the already-released caller buffer.
diff --git a/Modules/_bz2module.c b/Modules/_bz2module.c
index 798e9efc62..b08ac5e44e 100644
--- a/Modules/_bz2module.c
+++ b/Modules/_bz2module.c
@@ -595,6 +595,7 @@ decompress(BZ2Decompressor *d, char *data, size_t len, Py_ssize_t max_length)
return result;
error:
+ bzs->next_in = NULL;
Py_XDECREF(result);
return NULL;
}
diff --git a/Modules/_lzmamodule.c b/Modules/_lzmamodule.c
index 97453a2808..51106a6a07 100644
--- a/Modules/_lzmamodule.c
+++ b/Modules/_lzmamodule.c
@@ -1105,6 +1105,7 @@ decompress(Decompressor *d, uint8_t *data, size_t len, Py_ssize_t max_length)
return result;
error:
+ lzs->next_in = NULL;
Py_XDECREF(result);
return NULL;
}