New Chrome 0-day Under Active Attacks
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2020-15999 | Heap Buffer Overflow in FreeType Font Rendering in Google Chrome (CVE-2020-15999) Google Chrome bundles the open-source FreeType library for font rendering, and that library contains a heap buffer overflow (CWE-787, out-of-bounds write) in its Load_SBit_Png function. The flaw is triggered when the browser loads a crafted font containing a malicious PNG image embedded as embedded bitmap data, typically from a web page the victim visits, corrupting heap memory with attacker-controlled data. Successful exploitation can crash the browser or execute code in the renderer, and it was used in the wild as part of an exploit chain combined with CVE-2020-17087 (Windows kernel) and CVE-2020-16010 (Android) to escape the sandbox. Anyone running an affected Google Chrome release that ships the vulnerable FreeType code, across Windows, macOS, Linux, Chrome OS and Android, is affected, meaning effectively the entire Chrome install base at the time of disclosure. The vulnerability is confirmed exploited in the wild (listed in CISA's KEV catalog, added 2021-11-03; ransomware use unknown), Google patched it in Chrome 86.0.4240.111, no public proof-of-concept is known, and EPSS estimates a 44.3% probability of exploitation within 30 days (99th percentile). Do: Update Google Chrome to 86.0.4240.111 or later (any current stable-channel release satisfies this), and where other software bundles FreeType directly, update to FreeType 2.10.4 or later per the upstream fix. Because the bug was chained with CVE-2020-17087 on Windows and CVE-2020-16010 on Android, also apply the corresponding Microsoft Windows and Android updates to close the sandbox-escape chain. Use endpoint management to inventory browser versions and confirm no endpoints remain below the fixed release, as required by the CISA KEV catalog. | 9.6 | 44% | KEV PoC ×2 |
| masson the order of billions of users (Chrome's active user base exceeded ~3 billion at the time; the vulnerable FreeType code shipped in every affected release) |
Full article497 words · extracted from thehackernews.com · click to collapse
Swati KhandelwalOct 21, 2020
Attention readers, if you are using Google Chrome browser on your Windows, Mac, or Linux computers, you need to update your web browsing software immediately to the latest version Google released earlier today.
Google released Chrome version 86.0.4240.111 today to patch several security high-severity issues, including a zero-day vulnerability that has been exploited in the wild by attackers to hijack targeted computers.
Tracked as CVE-2020-15999, the actively exploited vulnerability is a type of memory-corruption flaw called heap buffer overflow in Freetype, a popular open source software development library for rendering fonts that comes packaged with Chrome.
The vulnerability was discovered and reported by security researcher Sergei Glazunov of Google Project Zero on October 19 and is subject to a seven-day public disclosure deadline due to the flaw being under active exploitation.
Glazunov also immediately reported the zero-day vulnerability to FreeType developers, who then developed an emergency patch to address the issue on October 20 with the release of FreeType 2.10.4.
Without revealing technical details of the vulnerability, the technical lead for Google's Project Zero Ben Hawkes warned on Twitter that while the team has only spotted an exploit targeting Chrome users, it's possible that other projects that use FreeType might also be vulnerable and are advised to deploy the fix included in FreeType version 2.10.4.
"While we only saw an exploit for Chrome, other users of freetype should adopt the fix discussed here: https://savannah.nongnu.org/bugs/?59308 -- the fix is also in today's stable release of FreeType 2.10.4," Hawkes writes.
According to details shared by Glazunov, the vulnerability exists in the FreeType's function "Load_SBit_Png," which processes PNG images embedded into fonts. It can be exploited by attackers to execute arbitrary code just by using specifically crafted fonts with embedded PNG images.
"The issue is that libpng uses the original 32-bit values, which are saved in `png_struct`. Therefore, if the original width and/or height are greater than 65535, the allocated buffer won't be able to fit the bitmap," Glazunov explained.
Glazunov also published a font file with a proof-of-concept exploit.
Google released Chrome 86.0.4240.111 as Chrome's "stable" version, which is available to all users, not just to opted-in early adopters, saying that the company is aware of reports that "an exploit for CVE-2020-15999 exists in the wild," but did not reveal further details of the active attacks.
Besides the FreeType zero-day vulnerability, Google also patched four other flaws in the latest Chrome update, three of which are high-risk vulnerabilities—an inappropriate implementation bug in Blink, a use after free bug in Chrome's media, and use after free bug in PDFium—and one medium-risk use after free issue in browser's printing function.
Although the Chrome web browser automatically notifies users about the latest available version, users are recommended to manually trigger the update process by going to "Help → About Google Chrome" from the menu.
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2020/10/chrome-zeroday-attacks.html