CVE-2019-7303
Snapd seccomp filter TIOCSTI ioctl bypass
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Snapd seccomp filter TIOCSTI ioctl bypass
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
CVE-2019-7303- CVSS 3.0
- 5.7 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L - Weakness
- CWE-628
- Updated
- 2026-11-02
EUVDEUVD-2019-16847
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
EUVD-2019-16847- CVSS 3.0
- 5.7 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hhhq-qgvm-w5hp No score
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict...
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
GHSA-hhhq-qgvm-w5hp- Updated
- 2026-11-02
NVD
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
CVE-2019-7303- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 3.0
- 5.7 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:P/A:N - Weakness
- CWE-628
- Updated
- 2026-11-02
OSV
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
CVE-2019-7303- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2019-7303
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
DEBIAN-CVE-2019-7303- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2019-7303
A vulnerability in the seccomp filters of Canonical snapd before version 2.37.4 allows a strict mode snap to insert characters into a terminal on a 64-bit host. The seccomp rules were generated to match 64-bit ioctl(2) commands on a 64-bit platform; however, the Linux kernel only uses the lower 32 bits to determine which ioctl(2) commands to run. This issue affects: Canonical snapd versions prior to 2.37.4.
- Record
UBUNTU-CVE-2019-7303- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 3.0
- 5.7 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L - CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVUSN-3917-1 No score
snapd vulnerability
The snapd default seccomp filter for strict mode snaps blocks the use of the ioctl() system call when used with TIOCSTI as the second argument to the system call. Jann Horn discovered that this restriction could be circumvented on 64 bit architectures. A malicious snap could exploit this to bypass intended access restrictions to insert characters into the terminal's input queue. On Ubuntu, snapd typically will have already automatically refreshed itself to snapd 2.37.4 which is unaffected.
- Record
USN-3917-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
snapdDebian:12 |
before 2.37.4-1 | 2.37.4-1 |
snapdDebian:13 |
before 2.37.4-1 | 2.37.4-1 |
snapdDebian:14 |
before 2.37.4-1 | 2.37.4-1 |
snapdUbuntu:14.04:LTS |
before 2.37.4~14.04.1, plus listed versions 2.21~14.04.22.22.2~14.042.22.3~14.042.22.6~14.042.23.1~14.04 Show 11 moreShow less2.24.1~14.042.25~14.042.26.10~14.042.27.5~14.042.28.5~14.042.29.4.2~14.042.32.3.2~14.042.32.9~14.042.33.1~14.042.34.2~14.042.34.2~14.04.1 |
2.37.4~14.04.1 |
snapdUbuntu:16.04:LTS |
before 2.37.4ubuntu0.1, plus listed versions 1.91.9.1.11.9.22.02.0.1 Show 31 moreShow less2.0.22.0.32.0.52.0.82.0.92.0.102.11+0.16.042.12+0.16.042.132.14.2~16.042.15.2ubuntu12.16ubuntu32.17.1ubuntu12.20.1ubuntu12.212.22.22.22.32.22.62.23.12.24.12.252.26.102.27.52.28.52.29.4.22.32.3.22.32.92.33.1ubuntu22.34.22.34.2ubuntu0.12.37.4 |
2.37.4ubuntu0.1 |
snapdUbuntu:18.04:LTS |
before 2.37.4+18.04.1, plus listed versions 2.28.5+17.102.29.4.1+18.042.29.4.2+18.042.31.1+18.042.32+18.04~pre5 Show 12 moreShow less2.32+18.04~pre62.32+18.042.32.3.2+18.042.32.5+18.042.32.8+18.042.32.9+18.042.33.1+18.04ubuntu22.34.2+18.042.34.2+18.04.12.37.1+18.042.37.1.1+18.042.37.4+18.04 |
2.37.4+18.04.1 |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Exploit-DB | snap - seccomp BBlacklist for TIOCSTI can be Circumvented | 2019-03-22 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, Exploit-DB, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-7303 is a medium vulnerability (CVSS 5.7) in Canonical Snapd, published March 21, 2019. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 3.70%, the 89th percentile. Fixed in snapd 2.37.4-1.