CVE-2023-1587: Avast and AVG Antivirus for Windows were susceptible to a NULL pointer dereference issue via RPC-interface

Routine

MEDIUM 5.8UPGRADEUPGRADE

CVE-2023-1587 is a medium-severity flaw (CVSS 5.8) affecting antivirus, anti-virus. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Avast and AVG Antivirus for Windows were susceptible to a NULL pointer dereference issue via RPC-interface. The issue was fixed with Avast and AVG Antivirus version 22.11

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	5.8 (Medium)
Attack vector	Local
Attack complexity	High
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.2% (top 89%)
CISA exploited list	No
Weakness	CWE-476
Published	2023-04-19
Last modified	2026-06-17

Publisher (CNA): NortonLifeLock Inc. · Vendor: avast · avg

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

Am I affected?

Timeline

2023-04-19 19:15 UTCPublished CVE record published
2026-06-17 05:28 UTCUpdated Record last modified

avast antivirus UPGRADE

Affected: >= 22.5 and < 22.11

Fixed in: 22.11

Safe to downgrade to: a release before 22.5

1. Check installed version

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

2. UPGRADE to 22.11 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade antivirus

Note

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

3. If no update is available yet, DOWNGRADE to a release before 22.5 (Debian / Ubuntu)

apt-cache madison antivirus sudo apt install antivirus=<VERSION_BEFORE_22.5> sudo apt-mark hold antivirus

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list antivirus sudo dnf downgrade antivirus-<VERSION_BEFORE_22.5> sudo dnf versionlock add antivirus

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.

avg anti-virus UPGRADE

Affected: >= 22.5 and < 22.11

Fixed in: 22.11

Safe to downgrade to: a release before 22.5

1. Check installed version

apt-cache policy anti-virus || rpm -q anti-virus || anti-virus --version

2. UPGRADE to 22.11 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade anti-virus

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade anti-virus

Note

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

3. If no update is available yet, DOWNGRADE to a release before 22.5 (Debian / Ubuntu)

apt-cache madison anti-virus sudo apt install anti-virus=<VERSION_BEFORE_22.5> sudo apt-mark hold anti-virus

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list anti-virus sudo dnf downgrade anti-virus-<VERSION_BEFORE_22.5> sudo dnf versionlock add anti-virus

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.

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-2023-1587?

antivirus: upgrade to 22.11; anti-virus: upgrade to 22.11. Exact commands for each OS are on this page.

Is CVE-2023-1587 being exploited?

CVE-2023-1587 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-2023-1587 affect?

CVE-2023-1587 affects antivirus, anti-virus. Severity is medium (CVSS 5.8). Avast and AVG Antivirus for Windows were susceptible to a NULL pointer dereference issue via RPC-interface. The issue was fixed with Avast and AVG Antivirus version 22.11

How urgent is CVE-2023-1587?

Priority 23/100. No elevated risk signals yet.

Software pages

Windows vulnerabilities

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References

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