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 044D358E2D8 for ; Fri, 11 Sep 2026 19:59:16 +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=1789156763; cv=none; b=ogSJFaGjsRjkE3GepoY0fHYnP3aUaG+mMXQ9nokpCfPR/a0BBE4+SBj5ndJfOH5ajR9nACOw4whkQ9vTJmXEut13BQbi/tnXfkfxiJTLRAf9bfVTe9x1QwuudPOaTGglSQpLrC3dZMmFylONbrcKMAojq5vvBitYWly+duHSJgk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156763; c=relaxed/simple; bh=BAcWMmShgO2U7jxhihZr5CRnf0960HUnjKFewhqVuOY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=kZr40qRTa6nZFapjwpPxBldF6PajaFyvkyGEADx6Akh2wW4tgVljIcMdhS7ZTcxShi4Zhh94Rx3KrMhstaC23w+4zGLwG6NRaRlrst7IWJQEkNXNkQrqC+Gj/IYh2MQVx1lFC+KUTjNBmZu5HoerLNfJxsfOcdCJjhej5zjilxg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cLQlHJ76; 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="cLQlHJ76" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2FB651F000FF; Fri, 11 Sep 2026 19:59:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156756; bh=tw5jF9z/e/AA+6CxzoKUW1nj3kf5DrCXy3xD2rxtCvw=; h=From:To:Cc:Subject:Date:Reply-To; b=cLQlHJ760ihNAlsac8WAjTGFkwKDdspOpuB30DvkrJFkmX5mSwz/uIx/Y57aRJ3ys eAXPSVmD85dBJSpCFIVCIodSPoR39dvT16DAOden2numLpTgErbJo8NAJIybcyH0xu 6Xxym3h8aJr3MbQmobHAlsb9E9aPCbuskaiiNBm4= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89622: HID: mcp2221: clear rxbuf after I2C/SMBus transfer completes Date: Fri, 11 Sep 2026 21:45:11 +0200 Message-ID: <2026091137-CVE-2026-89622-517b@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=2642; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=lIqA52M/07BwyjmqgSocP7Zrh2/RWwtajUjbwcBozho=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIgsZJ+e42Gh8i2c4J+1y/c55J0brvxay5lJ7762+K nbdefrljlgWBkEmBlkxRZYv23iO7q84pOhlaHsaZg4rE8gQBi5OAZjI+16G+fXWoWcjjvCdCHot 2nXozV4Nvw/2WgzzzNV1nus99ssNZ/xdGXgh/6h29dliAA== 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: HID: mcp2221: clear rxbuf after I2C/SMBus transfer completes mcp_i2c_smbus_read() stores the caller-supplied buffer pointer in mcp->rxbuf for the duration of a transfer but never clears it when the transfer finishes or times out. Once the caller frees or reuses the buffer, mcp->rxbuf becomes a dangling pointer. A delayed or spurious MCP2221_I2C_GET_DATA report can then drive mcp2221_raw_event() to memcpy device data into the freed memory, causing a write use-after-free. Route all return paths through a single exit point that clears mcp->rxbuf and mcp->rxbuf_size, so that the existing !mcp->rxbuf guard in the raw_event handler can reject any report arriving after the transfer has ended. The Linux kernel CVE team has assigned CVE-2026-89622 to this issue. Affected and fixed versions =========================== Issue introduced in 5.7 with commit 67a95c21463d066060b0f66d65a75d45bb386ffb and fixed in 6.18.51 with commit 03c34309eb1bce1b3b5f7c4a94b703f419120383 Issue introduced in 5.7 with commit 67a95c21463d066060b0f66d65a75d45bb386ffb and fixed in 7.2.4 with commit 968546b676d992dd1da3e057d40598231f725996 Issue introduced in 5.7 with commit 67a95c21463d066060b0f66d65a75d45bb386ffb and fixed in 7.3-rc1 with commit db2333f88729c8aae062cb171ed058725ff5c901 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-2026-89622 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/hid/hid-mcp2221.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/03c34309eb1bce1b3b5f7c4a94b703f419120383 https://git.kernel.org/stable/c/968546b676d992dd1da3e057d40598231f725996 https://git.kernel.org/stable/c/db2333f88729c8aae062cb171ed058725ff5c901