CVE-2018-8786: FreeRDP prior to version 2.0.0-rc4 contains an Integer Truncation that leads to a Heap-Based Buffer Overflow i

Q: How do I fix CVE-2018-8786?

freerdp: upgrade to newer than 1.2.0; ubuntu linux: mitigate or apply the listed mitigation; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2018-8786 being exploited?

CVE-2018-8786 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2018-8786 affect?

CVE-2018-8786 affects freerdp, ubuntu linux, debian linux. Severity is critical (CVSS 9.8). FreeRDP prior to version 2.0.0-rc4 contains an Integer Truncation that leads to a Heap-Based Buffer Overflow in function update_read_bitmap_update() and results in a memory corruption and probably even a remote code execution.

Q: How urgent is CVE-2018-8786?

Priority 73/100. Critical severity; EPSS top 5%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist

This week

CRITICAL 9.8REMOTEWATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2018-8786 is a critical-severity flaw (CVSS 9.8) affecting freerdp, ubuntu linux, debian linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

FreeRDP prior to version 2.0.0-rc4 contains an Integer Truncation that leads to a Heap-Based Buffer Overflow in function update_read_bitmap_update() and results in a memory corruption and probably even a remote code execution.

Why this priority

Critical severity
EPSS top 5%: very likely to be exploited
Public exploit reference
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	8.2% (top 5%)
CISA exploited list	No
Weakness	CWE-680, CWE-681, CWE-787
Published	2018-11-29
Last modified	2026-06-17

Publisher (CNA): Check Point Software Technologies Ltd. · Vendor: canonical · debian · fedoraproject · freerdp · redhat

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

Am I affected?

Timeline

2018-11-29 18:29 UTCPublished CVE record published
2026-06-17 02:05 UTCUpdated Record last modified

freerdp freerdp UPGRADE

Affected: <= 1.2.0 · 2.0.0 rc1 · 2.0.0 rc2 · 2.0.0 rc3

Fixed in: newer than 1.2.0

Safe to downgrade to: no unaffected older release

1. Check installed version

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

2. UPGRADE to newer than 1.2.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade freerdp

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade freerdp

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

canonical ubuntu linux MITIGATE

Affected: 14.04 · 16.04 · 18.04 · 18.10

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.

debian debian linux MITIGATE

Affected: 8.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

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.

fedoraproject fedora MITIGATE

Affected: 28

Fixed in: no fixed release known

Safe to downgrade to: a release before 28

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.

redhat enterprise linux desktop MITIGATE

Affected: 7.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.0

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.

redhat enterprise linux server MITIGATE

Affected: 7.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.0

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.

Exact fixes by distribution

A distro patch exists: prefer upgrading over downgrading.

Fedora 46 · copyparty · FIXED · 1.20.26-1.fc46 · FEDORA-2026-8fbe18458e · source

sudo dnf upgrade --advisory=FEDORA-2026-8fbe18458e

Fedora ELN · man-pages · FIXED · 6.20-1.eln159 · FEDORA-2026-f1f5fb11b4 · source

sudo dnf upgrade --advisory=FEDORA-2026-f1f5fb11b4

Debian 12 · freerdp2 · FIXED · 2.0.0~git20181120.1.e21b72c95+dfsg1-1

sudo apt update && sudo apt install --only-upgrade freerdp2 dpkg --compare-versions "$(dpkg-query -W -f='${Version}' freerdp2)" ge "2.0.0~git20181120.1.e21b72c95+dfsg1-1" && echo PATCHED || echo STILL-VULNERABLE

RHEL 7 · freerdp · FIXED · freerdp-1.0.2-15.el7_6.1

sudo dnf upgrade --advisory=RHSA-2019:0697 rpm -q freerdp

RHEL 6 · freerdp · DEFERRED

RHEL 8 · freerdp · NOT AFFECTED

Alpine 3.20 · freerdp · FIXED · freerdp-2.0.0_rc4-r0

apk add --upgrade freerdp apk info -v freerdp

Alpine 3.21 · freerdp · FIXED · freerdp-2.0.0_rc4-r0

apk add --upgrade freerdp apk info -v freerdp

Alpine 3.22 · freerdp · FIXED · freerdp-2.0.0_rc4-r0

apk add --upgrade freerdp apk info -v freerdp

Alpine 3.22 · freerdp2 · FIXED · freerdp2-2.0.0_rc4-r0

apk add --upgrade freerdp2 apk info -v freerdp2

Amazon Linux 2 · see advisory · FIXED · ALAS2-2019-1191 · source

sudo yum update --advisory=ALAS2-2019-1191

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Write-up: research.checkpoint.com/reverse-rdp-attack-code-execution-on-rdp-clients/
Write-up: usn.ubuntu.com/3845-1/

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-2018-8786?

freerdp: upgrade to newer than 1.2.0; ubuntu linux: mitigate or apply the listed mitigation; debian linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2018-8786 being exploited?

CVE-2018-8786 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-2018-8786 affect?

CVE-2018-8786 affects freerdp, ubuntu linux, debian linux. Severity is critical (CVSS 9.8). FreeRDP prior to version 2.0.0-rc4 contains an Integer Truncation that leads to a Heap-Based Buffer Overflow in function update_read_bitmap_update() and results in a memory corruption and probably even a remote code execution.

How urgent is CVE-2018-8786?

Priority 73/100. Critical severity; EPSS top 5%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Ubuntu vulnerabilities · Debian vulnerabilities

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References

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