Threat Intelligence Database

Multiple vulnerabilities have been identified in CUPS (Common Unix Printing System), a print spooler that allows local and remote users to utilize printing functions via the Internet Printing Protocol (IPP). These vulnerabilities affect versions up to and including 2.4.20. No CVSS score is provided, and no known exploits are reported in the wild. The vulnerabilities are documented by the Bundesamt für Sicherheit in der Informationstechnik (BSI) under advisory WID-SEC-W-2026-1968.

CVE-2026-41079 is a medium severity vulnerability in OpenPrinting CUPS versions prior to 2.4.17. It involves an out-of-bounds read triggered by a crafted SNMP response sent to the CUPS SNMP backend. This flaw allows reading up to 176 bytes beyond a stack buffer, leaking memory that is converted to UTF-8 and exposed as printer supply descriptions. These leaked strings can be viewed by authenticated users through IPP Get-Printer-Attributes responses and the CUPS web interface. The vulnerability does not impact integrity or availability and requires network adjacency but no privileges or user interaction. A fix is available in version 2.4.17.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, a use-after-free vulnerability exists in the CUPS scheduler (cupsd) when temporary printers are automatically deleted.cupsdDeleteTemporaryPrinters() in scheduler/printers.c calls cupsdDeletePrinter() without first expiring subscriptions that reference the printer, leaving cupsd_subscription_t.dest as a dangling pointer to freed heap memory. The dangling pointer is subsequently dereferenced at multiple code sites, causing a crash (denial of service) of the cupsd daemon. With heap grooming, this can be leveraged for code execution.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, an integer underflow vulnerability in _ppdCreateFromIPP() (cups/ppd-cache.c) allows any unprivileged local user to crash the cupsd root process by supplying a negative job-password-supported IPP attribute. The bounds check only caps the upper bound, so a negative value passes validation, is cast to size_t (wrapping to ~2^64), and is used as the length argument to memset() on a 33-byte stack buffer. This causes an immediate SIGSEGV in the cupsd root process. Combined with systemd's Restart=on-failure, an attacker can repeat the crash for sustained denial of service.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, in a network-exposed cupsd with a shared target queue, an unauthorized client can send a Print-Job to that shared PostScript queue without authentication. The server accepts a page-border value supplied as textWithoutLanguage, preserves an embedded newline through option escaping and reparse, and then reparses the resulting second-line PPD: text as a trusted scheduler control record. A follow-up raw print job can therefore make the server execute an attacker-chosen existing binary such as /usr/bin/vim as lp. At time of publication, there are no publicly available patches.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, there is a heap-based buffer overflow in the CUPS scheduler when building filter option strings from job attribute. At time of publication, there are no publicly available patches.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, the RSS notifier allows .. path traversal in notify-recipient-uri (e.g., rss:///../job.cache), letting a remote IPP client write RSS XML bytes outside CacheDir/rss (anywhere that is lp-writable). In particular, because CacheDir is group-writable by default (typically root:lp and mode 0770), the notifier (running as lp) can replace root-managed state files via temp-file + rename(). This PoC clobbers CacheDir/job.cache with RSS XML, and after restarting cupsd the scheduler fails to parse the job cache and previously queued jobs disappear. At time of publication, there are no publicly available patches.

CVE-2026-34990 is an improper authentication vulnerability in OpenPrinting CUPS versions 2.4.16 and earlier. A local unprivileged user can trick the CUPS daemon into authenticating to a malicious localhost IPP service using a reusable authorization token. This token allows the attacker to perform administrative requests locally, including creating a printer queue with a file URI that bypasses normal policy restrictions. Exploiting this flaw can lead to arbitrary root file overwrites, enabling privilege escalation to root. No patches or official fixes are available at the time of publication.

CVE-2026-27447 is an authorization bypass vulnerability in OpenPrinting CUPS versions 2.4.16 and earlier. The issue arises from case-insensitive username comparison during authorization checks in the CUPS daemon, allowing an unprivileged user to perform restricted operations by using a username differing only in letter case from an authorized user. No patches or official fixes are available at the time of publication. The vulnerability has a medium severity rating with a CVSS score of 4.8.

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. Prior to version 2.4.15, a client that connects to cupsd but sends slow messages, e.g.only one byte per second, delays cupsd as a whole, such that it becomes unusable by other clients. This issue has been patched in version 2.4.15.

MediumVulnerabilityGermanyFranceUnited Kingdom+5#cve#cve-2025-58436#cwe-400