Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
10 results
Jun 22, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-47242 · Other software · ruby · reported by GitHubMedium 5.8
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, when Net::IMAP#id is called with a hash argument, although the ID field value strings are correctly quoted (escaping quoted specials), they were not validated to prohibit CRLF sequences. While Net::IMAP#enable does process its arguments for aliases, it does not validate them as valid atoms (or as a list of valid atoms). The #to_s value is sent verbatim. Arguments to either command could be used by an attacker to inject arbitrary IMAP commands. This vulnerability is fixed in 0.6.5 and 0.5.15.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-47241 · Other software · ruby · reported by GitHubLow 2.1
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, several Net::IMAP commands accept a raw string argument which is only validated to prevent CRLF injection and then sent verbatim. If this string is derived from user-controlled input, an attacker can force the next command to be absorbed as a continuation of the first command. This will cause the first command to eventually fail, but also prevents it from returning until another command is sent (from another thread). That other command will not return until the connection is closed. This vulnerability is fixed in 0.6.5 and 0.5.15.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-47240 · Other software · ruby · reported by GitHubMedium 5.8
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, several Net::IMAP commands accept a "raw data" argument that is sent verbatim after validation to prevent command injection. However, if a server does not support non-synchronizing literals, it may still be possible to inject arbitrary IMAP commands inside non-synchronizing literals. A server without support for non-synchronizing literals may interpret the "+}\r\n" as the end of a malformed command line and respond with a tagged BAD. In that case, the contents of the literal will be interpreted as one or more new pipelined commands, allowing a CRLF command injection attack to succeed. This affects criteria for #search and #uid_search; search_keys for #sort, #thread, #uid_sort, and #uid_thread; and attr for #fetch and #uid_fetch. This vulnerability is fixed in 0.6.5 and 0.5.15.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 9, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-42258 · Other software · ruby · reported by GitHubMedium 5.8
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, symbol arguments to commands are vulnerable to a CRLF Injection / IMAP Command injection via Symbol arguments passed to IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 9, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-42257 · Other software · ruby · reported by GitHubMedium 5.8
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this string is derived from user-controlled input, it may contain contain CRLF sequences, which an attacker can use to inject arbitrary IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 9, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-42256 · Other software · ruby · reported by GitHubMedium 6
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. From versions 0.4.0 to before 0.4.24, 0.5.0 to before 0.5.14, and 0.6.0 to before 0.6.4, when authenticating a connection with SCRAM-SHA1 or SCRAM-SHA256, a hostile server can perform a computational denial-of-service attack on the client process by sending a big iteration count value. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 9, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-42246 · Other software · ruby · reported by GitHubHigh 7.6
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 9, 2026Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2026-42245 · Other software · ruby · reported by GitHubLow 2.3
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, Net::IMAP::ResponseReader has quadratic time complexity when reading large responses containing many string literals. A hostile server can send responses which are crafted to exhaust the client's CPU for a denial of service attack. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 28, 2025Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2025-43857 · Other software · ruby · reported by GitHubMedium 6
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.5.7, 0.4.20, 0.3.9, and 0.2.5, there is a possibility for denial of service by memory exhaustion when net-imap reads server responses. At any time while the client is connected, a malicious server can send can send a "literal" byte count, which is automatically read by the client's receiver thread. The response reader immediately allocates memory for the number of bytes indicated by the server response. This should not be an issue when securely connecting to trusted IMAP servers that are well-behaved. It can affect insecure connections and buggy, untrusted, or compromised servers (for example, connecting to a user supplied hostname). This issue has been patched in versions 0.5.7, 0.4.20, 0.3.9, and 0.2.5.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Feb 10, 2025Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby.CVE-2025-25186 · Other software · ruby · reported by GitHubMedium 6.5
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Starting in version 0.3.2 and prior to versions 0.3.8, 0.4.19, and 0.5.6, there is a possibility for denial of service by memory exhaustion in `net-imap`'s response parser. At any time while the client is connected, a malicious server can send can send highly compressed `uid-set` data which is automatically read by the client's receiver thread. The response parser uses `Range#to_a` to convert the `uid-set` data into arrays of integers, with no limitation on the expanded size of the ranges. Versions 0.3.8, 0.4.19, 0.5.6, and higher fix this issue. Additional details for proper configuration of fixed versions and backward compatibility are available in the GitHub Security Advisory.
- Product
- net-imap
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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