Week in review: Critical git vulnerabilities, increasingly malicious Google Search ads

Git is distributed revision control system. `git log` can display commits in an arbitrary format using its `--format` specifiers. This functionality is also exposed to `git archive` via the `export-subst` gitattribute. When processing the padding operators, there is a integer overflow in `pretty.c::format_and_pad_commit()` where a `size_t` is stored improperly as an `int`, and then added as an offset to a `memcpy()`. This overflow can be triggered directly by a user running a command which invokes the commit formatting machinery (e.g., `git log --format=...`). It may also be triggered indirectly through git archive via the export-subst mechanism, which expands format specifiers inside of files within the repository during a git archive. This integer overflow can result in arbitrary heap writes, which may result in arbitrary code execution. The problem has been patched in the versions published on 2023-01-17, going back to v2.30.7. Users are advised to upgrade. Users who are unable to upgrade should disable `git archive` in untrusted repositories. If you expose git archive via `git daemon`, disable it by running `git config --global daemon.uploadArch false`.

Cacti, a widely used open-source network monitoring and graphing platform, contains a command injection flaw (CWE-74) that lets a completely unauthenticated attacker execute arbitrary commands on the Cacti server. The bug is reachable through the web-facing remote_agent.php script, where an attacker can spoof a trusted poller address (e.g., via a forwarded-client HTTP header) to bypass authentication and inject shell metacharacters into parameters used to build polling commands. Successful exploitation yields code execution in the context of the web server, giving an attacker a foothold on a monitoring system that typically has broad network visibility and stored credentials for many managed devices. Any Cacti deployment running vulnerable code is affected, with internet-exposed instances at greatest risk. Exploitation is confirmed in the wild — the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2023-02-16, and EPSS assigns it a 99.8% probability of exploitation.

Do: Apply CISA's required action by upgrading Cacti to the patched release (1.2.23 or later per vendor guidance). Until patched, restrict access to remote_agent.php to known poller source addresses and monitor web access and Cacti logs for signs of exploitation. Prioritize internet-exposed Cacti servers, since KEV listing confirms active exploitation and ransomware use is listed as unknown.

CVE-2022-47966 is a critical (CVSS 9.8), unauthenticated remote code execution flaw in roughly two dozen Zoho ManageEngine on-premise products caused by their bundled Apache Santuario xmlsec (XML Security for Java) 1.4.1 library, in which the XSLT features leave security protections to the application and ManageEngine did not provide them. An attacker triggers the flaw by sending a crafted SAML response containing a malicious XSLT transform to the SAML single sign-on (SSO) endpoint; exploitation is only possible if SAML SSO has ever been configured for the product (for some products, SAML SSO must be currently active). Successful exploitation yields arbitrary code execution in the context of the affected ManageEngine application, typically full compromise of the server and a foothold into the wider enterprise network. Any organization running an affected product version with SAML SSO enabled is affected, with internet-exposed ITSM/identity-management servers the most likely targets. Exploitation is confirmed in the wild: the flaw is in CISA KEV with known ransomware use, Rapid7 reported broad attacker interest, North Korea's Lazarus Group used it to deploy QuiteRAT, and Iranian government-backed actors have targeted U.S. energy and transit-sector organizations.

Do: Apply vendor updates immediately, upgrading each installed product to at least the fixed version listed (e.g., ServiceDesk Plus 14004+, ADSelfService Plus 6211+, Endpoint Central/Endpoint Central MSP 10.1.2228.11+, Password Manager Pro 12124+, ServiceDesk Plus MSP 13001+, ADAudit Plus 7081+, ADManager Plus 7162+, AD360 4310+); this is a CISA KEV required action. As an interim mitigation, disable or restrict SAML SSO (or limit access to the product's SSO endpoints), since SAML SSO must have been configured for exploitation. Prioritize patching internet-exposed instances and review those servers for signs of compromise, given documented use by Lazarus Group, ransomware operators, and Iranian nation-state actors.

On Netcomm router models NF20MESH, NF20, and NL1902 a stack based buffer overflow affects the sessionKey parameter. By providing a specific number of bytes, the instruction pointer is able to be overwritten on the stack and crashes the application at a known location.