CVE-2019-13272
CVE-2019-13272 is a security flaw in Linux Kernel, the core of Linux, which runs most servers, Android phones and many home routers. Someone who already has a foothold can use Linux Kernel to take full control of the machine. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 10 Dec 2021.[1]
Linux Kernel is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff. Linux has published a fix or advice.
Description
CISA calls it an improper privilege management in Linux Kernel. In its words: “Kernel/ptrace.c in Linux kernel mishandles contains an improper privilege management vulnerability that allows local users to obtain root access.”[1]
The CVE record adds: “In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.”[2]
The underlying weakness is improper privilege management (CWE-269), in MITRE’s list of common software weaknesses.
It scores 7.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Linux’s advisory has them[3]. CISA names the product as Linux Kernel.
Most families won’t have Linux Kernel; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 10 Dec 2021, 877 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 10 Jun 2022 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 52%. That’s in the top 2% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Linux has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.Linux Kernel is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 10 Jun 2022 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 7.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 52%.[4] |
See also
Other Linux Kernel flaws
- CVE-2026-46300: missing initialization of a variable ·
- CVE-2026-53266: out-of-bounds write ·
- CVE-2025-39964: race condition ·
- CVE-2025-39682: improper check for unusual or exceptional conditions ·
- CVE-2026-53362: unspecified ·
- CVE-2022-0995: out-of-bounds write ·
Other improper privilege management flaws
- CVE-2026-102490, Zammad GmbH Zammad: improper privilege management ·
- CVE-2026-84869, ConnectWise ScreenConnect: improper privilege management and missing authorization ·
- CVE-2026-46817, Oracle E-Business Suite: improper privilege management ·
- CVE-2026-21533, Microsoft Windows: improper privilege management ·
- CVE-2024-8068, Citrix Session Recording: improper privilege management ·
Added the same day
- CVE-2021-44515, Zoho Desktop Central: authentication bypass ·
- CVE-2021-44228, Apache Log4j2: remote code execution ·
- CVE-2021-44168, Fortinet FortiOS: arbitrary file download ·
- CVE-2021-35394, Realtek Jungle Software Development Kit (SDK): jungle SDK remote code execution ·
- CVE-2020-8816, Pi-hole AdminLTE: remote code execution ·
Every Linux flaw on CISA’s list · Everything added in December 2021
References
- ^ Cybersecurity and Infrastructure Security Agency. “Linux Kernel Improper Privilege Management Vulnerability”. Known Exploited Vulnerabilities Catalog, added 10 Dec 2021.
- ^ National Institute of Standards and Technology. “CVE-2019-13272 Detail”. National Vulnerability Database, published 17 Jul 2019.
- ^ Linux. Advisories and fixes: bugzilla.redhat.com, bugzilla.suse.com, cdn.kernel.org, git.kernel.org, lists.fedoraproject.org.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.522, percentile 99.0, 31 Oct 2026.
- CVE Program. “CVE-2019-13272”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.