CUPS has a use-after-free in `cupsdDeleteTemporaryPrinters` via dangling subscription pointer
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 fixed, 6 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| OpenPrinting | cups | up to 2.4.16 | — | No fix listed | CNA |
- cups VendorOpenPrinting Affected up to 2.4.16 Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:openprinting:cups:*:*:*:*:*:*:*:* | up to 2.4.16 | Vulnerable | OpenPrinting |
- cpe:2.3:a:openprinting:cups:*:*:*:*:*:*:*:* Versions up to 2.4.16 Vulnerable ·OpenPrinting
Remediation
Red Hat 1 advisory
- RHSA-2026:8814 Released 2026-04-17 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images cups-2.4.17-1.hum1@aarch64, cups-2.4.17-1.hum1@src, cups-2.4.17-1.hum1@x86_64 +14
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Fixed | RHSA-2026:8814 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-39316
References
More OpenPrinting Cups vulnerabilities
- TI-2025-35903 cups has Authentication bypass with AuthType Negotiate CVSS 3.1HIGH 8.0
- TI-2023-17077 CUPS vulnerable to use-after-free in cupsdAcceptClient() CVSS 3.1HIGH 7.1
- TI-2026-27200 Path traversal in OpenPrinting cups CVSS 3.1MEDIUM 6.5
- TI-2023-04157 OpenPrinting CUPS/libppd Postscript Parsing Heap Overflow CVSS 3.1HIGH 7.0
- TI-2026-74874 Path traversal in OpenPrinting CUPS banner handling discloses files CVSS 3.1MEDIUM 5.3
- TI-2026-27201 OpenPrinting CUPS: Heap overflow in `get_options()` CVSS 3.1MEDIUM 5.3
Sources
- CVE-2026-39316 · CVE Program
- CVE-2026-39316 · NVD
- FIRST EPSS
- CVE-2026-39316 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences