CVE-2020-15702: TOCTOU Race Condition vulnerability in apport allows a local attacker to escalate privileges and execute arbit

This month

HIGH 7.0WATCHLISTDOWNGRADEMITIGATE

CVE-2020-15702 is a high-severity flaw (CVSS 7.0) affecting apport, ubuntu linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

TOCTOU Race Condition vulnerability in apport allows a local attacker to escalate privileges and execute arbitrary code. An attacker may exit the crashed process and exploit PID recycling to spawn a root process with the same PID as the crashed process, which can then be used to escalate privileges. Fixed in 2.20.1-0ubuntu2.24, 2.20.9 versions prior to 2.20.9-0ubuntu7.16 and 2.20.11 versions prior to 2.20.11-0ubuntu27.6. Was ZDI-CAN-11234.

Why this priority

High severity
On your watchlist

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.0 (High)
Attack vector	Local
Attack complexity	High
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.5% (top 57%)
CISA exploited list	No
Weakness	CWE-367
Published	2020-08-06
Last modified	2026-06-17

Publisher (CNA): Canonical Ltd. · Vendor: canonical

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2020-08-06 23:15 UTCPublished CVE record published
2026-06-17 02:57 UTCUpdated Record last modified

canonical apport DOWNGRADE

Affected: 2.20.11-0ubuntu8 · 2.20.11-0ubuntu9 · 2.20.11-0ubuntu10 · 2.20.11-0ubuntu11 · 2.20.11-0ubuntu12 · 2.20.11-0ubuntu13 · 2.20.11-0ubuntu14 · 2.20.11-0ubuntu15

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.19.1-0ubuntu3

1. Check installed version

apt-cache policy apport || rpm -q apport || apport --version

2. No fixed release: DOWNGRADE to a release before 2.19.1-0ubuntu3 (Debian / Ubuntu)

apt-cache madison apport sudo apt install apport=<VERSION_BEFORE_2.19.1-0ubuntu3> sudo apt-mark hold apport

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list apport sudo dnf downgrade apport-<VERSION_BEFORE_2.19.1-0ubuntu3> sudo dnf versionlock add apport

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

canonical ubuntu linux MITIGATE

Affected: 14.04

Fixed in: no fixed release known

Safe to downgrade to: a release before 14.04

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-15702?

apport: downgrade or apply the listed mitigation; ubuntu linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-15702 being exploited?

CVE-2020-15702 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-15702 affect?

CVE-2020-15702 affects apport, ubuntu linux. Severity is high (CVSS 7.0). TOCTOU Race Condition vulnerability in apport allows a local attacker to escalate privileges and execute arbitrary code. An attacker may exit the crashed process and exploit PID recycling to spawn a root process with the same PID as the cra

How urgent is CVE-2020-15702?

Priority 40/100. High severity; On your watchlist

Software pages

Ubuntu vulnerabilities

Related CVEs

CVE-2025-5467 LOW 3.3 UPGRADE It was discovered that process_crash() in data/apport in Canonical's Apport crash reporting tool may create cr
CVE-2025-5054 MEDIUM 4.7 UPGRADE MITIGATE Race condition in Canonical apport up to and including 2.32.0 allows a local attacker to leak sensitive inform
CVE-2023-1326 HIGH 7.7 UPGRADE MITIGATE A privilege escalation attack was found in apport-cli 2.26.0 and earlier which is similar to CVE-2023-26604
CVE-2022-28653 HIGH 7.5 UPGRADE Users can consume unlimited disk space in /var/crash
CVE-2022-1242 HIGH 7.8 UPGRADE MITIGATE Apport can be tricked into connecting to arbitrary sockets as the root user

References

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