From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 553063A3E8C for ; Sun, 19 Jul 2026 15:03:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784473435; cv=none; b=q8TiP/qsSgNa5lyHAwa1fO88YTDq3z5mZJ8Oo7rK0RrFUJRg/mcpJi0GyZDFqPN9hFiAdf9OOUgSpmQ4LJQblBQmpA3/jW5CgpXipTqcbJa5mN6mqJtcPmVxAO9USIyM0kQeaPXvdTgo6X8qBgP3Za6DWT/pnNY8c1nGUsK92fc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784473435; c=relaxed/simple; bh=HE+7dEP9wFceMxbCiua4+gO+af5aaqUvopWnTHYPHoI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=WYhRRh+3JJdfKPq+QNSZKhMmqMI/kWSCdwkSb//nAMlW1A4U/vnfpkZIk1p469VWrJ7G0TSWzccO3TU4PXsflkzuLKPeGRksiuDSDl4lGuXxOX9WNxwEqlEpiiCc/dM4rcFTqJbUpfxvKhxN/VlvHnQJD+bSvBB7rXSgs6H5gqo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GBEZ22HB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="GBEZ22HB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA51B1F000E9; Sun, 19 Jul 2026 15:03:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784473434; bh=fG0wlWRoxXHTqPxX34ZZ8Cb0zUTWWgOSnLZnMP/tsUo=; h=From:To:Cc:Subject:Date:Reply-To; b=GBEZ22HB5dHcQBh5jzZKqXofGkfEBk6d1EC+GaTMZRXdZKVOQrmUynVqoKaxTCvk5 f6vq3omNfQYpBhLTDWaoKrArVzPbm6O/qfd+1wc0DLWrArcQOOJacF8UMBEPJfZ8mE IJkiwKw5/TdAozQZMcHU2/FNV6tpu5MDGMsjez1U= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-63993: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu() Date: Sun, 19 Jul 2026 16:57:33 +0200 Message-ID: <2026071905-CVE-2026-63993-165e@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3371; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=OARhhh+YxFdNyrEayhbMKo7ikpGEHkuaVaXLHmY3xcM=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkxT1tXLa8/GSvwbg+niV7K74U3T365mXaFqTTm0x6Gt i+PKtQWdcSyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBEvK4wzA+N9Zhq+pdZ1vc7 h/LVjxVerGpmHxnmcLyMyo1tOSBqfs6/++dVxzbjr6+PAQA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu() skb_tunnel_check_pmtu() can change skb->head. Reusing old_iph afer skb_tunnel_check_pmtu() can cause an UAF. Use instead ip_hdr(skb) as done in drivers/net/bareudp.c and drivers/net/geneve.c. Found by Sashiko. The Linux kernel CVE team has assigned CVE-2026-63993 to this issue. Affected and fixed versions =========================== Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 5.10.259 with commit 6b8bfce9d2f774d2c2243e0248e03efb99bba6c0 Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 5.15.210 with commit 9257f56ac47ef1976bcd056cf986a9988eeec67a Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 6.1.176 with commit 8d435d68d71fb875876b722f4136caf74f2f48bd Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 6.6.143 with commit dc3bfa050f873371e745bdf478b1f5b738e5733d Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 6.12.93 with commit 609e63312c29aad18026a1d3222e123d4b6b0feb Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 6.18.35 with commit 5303925e360527243b46a440a04667826bbc72b7 Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 7.0.12 with commit a493efd4336cf19122ae0e4cbb3d31b32d70deea Issue introduced in 5.9 with commit 4cb47a8644cc9eb8ec81190a50e79e6530d0297f and fixed in 7.1 with commit 7d9ef0cb271555d8cf39fefe6c981e1493b25ecf Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-63993 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: drivers/net/vxlan/vxlan_core.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/6b8bfce9d2f774d2c2243e0248e03efb99bba6c0 https://git.kernel.org/stable/c/9257f56ac47ef1976bcd056cf986a9988eeec67a https://git.kernel.org/stable/c/8d435d68d71fb875876b722f4136caf74f2f48bd https://git.kernel.org/stable/c/dc3bfa050f873371e745bdf478b1f5b738e5733d https://git.kernel.org/stable/c/609e63312c29aad18026a1d3222e123d4b6b0feb https://git.kernel.org/stable/c/5303925e360527243b46a440a04667826bbc72b7 https://git.kernel.org/stable/c/a493efd4336cf19122ae0e4cbb3d31b32d70deea https://git.kernel.org/stable/c/7d9ef0cb271555d8cf39fefe6c981e1493b25ecf