That vulnerability, according to a report on the data breach by William Baird & Co., was in a popular open-source software package called Apache Struts, which is a programming framework for building web applications in Java. Two vulnerabilities in Struts have been discovered so far in 2017. One was announced in March, and another was announced earlier this week on Sept. 4. At the moment, it’s unclear which vulnerability the Baird report was referring to.
Source: The hackers who broke into Equifax exploited a flaw in open-source server software — Quartz
The bug specifically affects a popular plugin called REST, which developers use to handle web requests, like data sent to a server from a form a user has filled out. The vulnerability relates to how Struts parses that kind of data and converts it into information that can be interpreted by the Java programming language. When the vulnerability is successfully exploited, malicious code can be hidden inside of such data, and executed when Struts attempts to convert it.
I cannot recall a previous data breach in which the breached company’s public outreach and response has been so haphazard and ill-conceived as the one coming right now from big-three credit bureau Equifax, which rather clumsily announced Thursday that an intrusion jeopardized Social security numbers and other information on 143 million Americans.
Source: Equifax Breach Response Turns Dumpster Fire — Krebs on Security
So in order to trigger this behaviour, someone with root-level privileges needs to edit a Unit file and enter a “invalid username”, in this case one that starts with a digit.
But you need root level privileges to edit the file in the first place and to reload systemd to make use of that Unit file.
Source: Giving perspective on systemd’s “usernames that start with digit get root privileges”-bug
It’s an obvious bug (at least on RHEL/CentOS 7), since a valid username does not get accepted by systemd so it triggers unexpected behaviour by launching services as root.
However, it isn’t as bad as it sounds and does not grant any username with a digit immediate root access.
To exploit the flaw, Caballero says that an attacker can use server redirect requests combined with data URIs, which would allow him to confuse Edge’s SOP filter and load unauthorized resources on sensitive domains. The expert explains the attack step by step on his blog.
In the end, the attacker will be able to inject a password form on another domain, which the built-in Edge password manager will automatically fill in with the user’s credentials for that domain. Below is a video of the attack.
Source: Edge Security Flaw Allows Theft of Facebook and Twitter Credentials
According to Scheel, the problem is that the HbbTV standard, carried by DVB-T signals and supported by all smart TVS, allows the sending of commands that tell smart TVs to access and load a website in the background.
Knowing this, Scheel developed two exploits he hosted on his own website, which when loaded in the TV’s built-in browser would execute malicious code, gain root access, and effectively take over the device.
Source: About 90% of Smart TVs Vulnerable to Remote Hacking via Rogue TV Signals
The (presumably ancient) code has a bug, though: it does not verify the syntax of the user name. RFC 959 specifies that a username may consist of a sequence of any of the 128 ASCII characters except
<LF>. Guess what the JRE implementers forgot? Exactly − to check for the presence of
<LF>. This means that if we put
%0D%0A anywhere in the user part of the URL (or the password part for that matter), we can terminate the USER (or PASS) command and inject a new command into the FTP session.
Source: SMTP over XXE − how to send emails using Java’s XML parser – shift or die
So, if we send a
USER command to a mail server instead of a FTP server, it will answer with an error code (since
USER is not a valid SMTP command), but let us continue with our session. Combined with the bug mentioned above, this allows us to send arbitrary SMTP commands, which allows us to send emails.
The full story is admittedly lengthy, clocking in at over 8000 words, but worth the time to understand how botnet wranglers make money siccing their zombie device armies on unsuspecting targets. The sources that pointed Krebs to Anna Senpai’s identity were involved in using botnets on behalf of shadowy clients, unleashing them on security companies protecting lucrative Minecraft servers that host thousands of players. When their online gaming is obstructed — say, by repeated and annoying DDoS attacks — players leave, giving servers an incentive to jump ship to whichever security provider can ensure protection…in this case, providers that arranged for the botnet attacks in the first place.
Source: Krebs pinpoints the likely author of the Mirai botnet
The exploit ending in .flac works as a drive-by attack when a Fedora 25 user visits a booby-trapped webpage. With nothing more than a click required, the file will open the desktop calculator. With modification, it could load any code an attacker chooses and execute it with the same system privileges afforded to the user. While users typically don’t have the same unfettered system privileges granted to root, the ones they do have are plenty powerful.
Source: 0-days hitting Fedora and Ubuntu open desktops to a world of hurt
Here’s a blurb from the researcher’s blog post about this:
Resolving all the above, I present here a full, working, reliable, 0day exploit for current Linux distributions (Ubuntu 16.04 LTS and Fedora 25). It’s a full drive-by download in the context of Fedora. It abuses cascading subtle side effects of an emulation misstep that at first appears extremely difficult to exploit but ends up presenting beautiful and 100% reliable exploitation possibilities.
Source: Redux: compromising Linux using… SNES Ricoh 5A22 processor opcodes?!
The vulnerability, a variety known as a race condition, was found in the way Linux memory handles a duplication technique called copy on write. Untrusted users can exploit it to gain highly privileged write-access rights to memory mappings that would normally be read-only. More technical details about the vulnerability and exploit are available here, here, and here. Using the acronym derived from copy on write, some researchers have dubbed the vulnerability Dirty COW.
Source: “Most serious” Linux privilege-escalation bug ever is under active exploit (updated)
The location of PAC files can be discovered through WPAD in several ways: through a special Dynamic Host Configuration Protocol (DHCP) option, through local Domain Name System (DNS) lookups, or through Link-Local Multicast Name Resolution (LLMNR).
Source: Disable WPAD now or have your accounts and private data compromised | CSO Online
The researchers recommended computer users disable the protocol. “No seriously, turn off WPAD!” one of their presentation slides said. “If you still need to use PAC files, turn off WPAD and configure an explicit URL for your PAC script; and serve it over HTTPS or from a local file.”
From Slashdot comments:
To prevent Windows from tracking which network support WPAD, you need to make a simple registry change:
Click the Start button, and in the search field, type in “regedit”, then select “regedit.exe” from the list of results
Navigate through the tree to “HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Wpad”
Once you have the “Wpad” folder selected, right click in the right pane, and click on “New -> DWORD (32-Bit Value)”
Name this new value “WpadOverride”
Double click the new “WpadOverride” value to edit it
In the “Value data” field, replace the “0” with a “1”, then click “OK”
Reboot the computer