From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 6488A3858C62; Tue, 7 Feb 2023 15:57:33 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 6488A3858C62 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1675785453; bh=j31sNDDhPlgzbM3W3cTA7/WN6766OzJbkoZRJK3IsbY=; h=From:To:Subject:Date:In-Reply-To:References:From; b=AiuNxP0ZB0rJ3VvabU2pvfFoG1qmwpPQU0wrrOa3VvXULEGMyHfWNtMrij24hO5fv rY2hmSwj/Zy2lTN3EqhN5V/WwyBA1Bf5dcIWhe5vailqoCy3FSDq4rIQSQmwj2ksl8 soNjM23M0Wl7AmNDmvBdnl2T5vQSLQ49FL+fH7Ic= From: "leo at yuriev dot ru" To: glibc-bugs@sourceware.org Subject: [Bug libc/29444] gmon memory corruption due wrong calculation of required buffer size Date: Tue, 07 Feb 2023 15:57:32 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: libc X-Bugzilla-Version: 2.38 X-Bugzilla-Keywords: X-Bugzilla-Severity: minor X-Bugzilla-Who: leo at yuriev dot ru X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: security- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D29444 --- Comment #12 from Leo Yuriev --- (In reply to Siddhesh Poyarekar from comment #11) > The inputs that induce this buffer overflow are basically addresses of the > running application that is built with gmon enabled *and* with the patch = for > bug 29438, so it's basically trusted input or input that needs an actual > security flaw to be compromised or controlled. The bug needs to be fixed, > but there's no security issue here. The patch for Bug 29438 not needed to exploitation, but gmon must be enable= d. Initially I discovered this issue while working on Bug 29438. But later it was re-noticed in another environment, where it is exploitable. Briefly: 1) Prerequirement: - a web service users gmon to collect statistics on the performance of its module(s); - OR an attacker can enable the collection of such statistics; 2) By manipulating requests, the attacker achieves a function call that is = at the end of the monitored addresses and is usually never called. T 3) The attacker continue an attack using memory corruption. Yes, this is a very specific scenario with a very low probability of exploitation. However, we reproduced it in a prepared environment. --=20 You are receiving this mail because: You are on the CC list for the bug.=