SB2026052033 - Anolis OS update for cups
Published: May 20, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Improper input validation (CVE-ID: CVE-2026-34978)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to overwrite arbitrary files within the CUPS CacheDir, including critical state files such as job.cache.
The vulnerability exists due to improper path validation in the RSS notifier component when processing attacker-controlled notify-recipient-uri values in IPP subscription requests. A remote attacker can send a specially crafted IPP request with a notify-recipient-uri containing directory traversal sequences (e.g., "rss:///../job.cache") to overwrite files outside the intended CacheDir/rss directory, leading to integrity and availability impacts.
The vulnerability specifically affects systems where the RSS notifier is enabled and untrusted clients can submit IPP Print-Job or Create-Printer-Subscription requests with subscription attributes. The default configuration with group-writable CacheDir (root:lp, 0770) enables overwriting of root-managed files via atomic rename operations performed by the lp-running notifier.
2) Heap-based buffer overflow (CVE-ID: CVE-2026-34979)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper input validation in the CUPS scheduler when processing IPP job attributes. A remote attacker can send a specially crafted IPP request with large URI attributes to trigger a heap-based buffer overflow in the `get_options()` function, leading to memory corruption and a crash of the `cupsd` service.
The vulnerability specifically arises because the size calculation for the options string uses `ipp_length()`, which excludes URI attributes, but the serialization process still writes URI attributes such as `job-uuid` and `job-authorization-uri` without bounds checking.
3) Improper input validation (CVE-ID: CVE-2026-34980)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Amber
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to improper input validation in CUPS PostScript queue processing when handling Print-Job requests with crafted page-border attributes. A remote attacker can send a specially crafted Print-Job request containing a newline-injected page-border value to cause a PPD configuration injection, leading to arbitrary filter execution as the lp user.
The affected system must have a shared PostScript queue enabled and be exposed to the network. The attacker does not require authentication or prior privileges.
Remediation
Install update from vendor's website.