PatchTheCVECVE-2017-5645: In Apache Log4j 2.x before 2.8.2, when using the TCP socket server or UDP socket server to receive serialized
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CRITICAL 9.8REMOTEWATCHLISTUPGRADEMITIGATEMITIGATE
CVE-2017-5645 is a critical-severity flaw (CVSS 9.8) affecting log4j, oncommand api services, oncommand insight. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
In Apache Log4j 2.x before 2.8.2, when using the TCP socket server or UDP socket server to receive serialized log events from another application, a specially crafted binary payload can be sent that, when deserialized, can execute arbitrary code.
Why this priority
- Critical severity
- EPSS top 1%: very likely to be exploited
- Public exploit reference
- CISA SSVC: automatable with total technical impact
- 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 | 89.4% (top 1%) |
| CISA exploited list | No |
| Weakness | CWE-502 |
| Published | 2017-04-17 |
| Last modified | 2026-10-08 |
Last updated 2026-10-08 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
apache log4j UPGRADE
Affected: >= 2.0 and < 2.8.2
Fixed in: 2.8.2
Safe to downgrade to: a release before 2.0
1. Check installed version
apt-cache policy log4j || rpm -q log4j || log4j --version
2. UPGRADE to 2.8.2 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade log4j
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade log4j
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 2.0 (Debian / Ubuntu)
apt-cache madison log4j
sudo apt install log4j=<VERSION_BEFORE_2.0>
sudo apt-mark hold log4j
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list log4j
sudo dnf downgrade log4j-<VERSION_BEFORE_2.0>
sudo dnf versionlock add log4j
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.
netapp oncommand api services MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy oncommand-api-services || rpm -q oncommand-api-services || oncommand-api-services --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
netapp oncommand insight MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy oncommand-insight || rpm -q oncommand-insight || oncommand-insight --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
netapp oncommand workflow automation MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy oncommand-workflow-automation || rpm -q oncommand-workflow-automation || oncommand-workflow-automation --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
netapp service level manager MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy service-level-manager || rpm -q service-level-manager || service-level-manager --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
netapp snapcenter MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy snapcenter || rpm -q snapcenter || snapcenter --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
Exact fixes by distribution
A distro patch exists: prefer upgrading over downgrading.
Maven · org.apache.logging.log4j:log4j · FIXED · 2.8.2 · vulnerable: >= 2.0, < 2.8.2 · source
Set org.apache.logging.log4j:log4j to 2.8.2 or later in pom.xml or build.gradle, then rebuild and redeploy.
Maven · org.apache.logging.log4j:log4j-core · FIXED · 2.8.2 · vulnerable: >= 2.0, < 2.8.2 · source
Set org.apache.logging.log4j:log4j-core to 2.8.2 or later in pom.xml or build.gradle, then rebuild and redeploy.
Fedora ELN · makedumpfile · FIXED · 1.8.0-1.eln159 · FEDORA-2026-3bf4582b1f · source
sudo dnf upgrade --advisory=FEDORA-2026-3bf4582b1f
Fedora 46 · python-resend · FIXED · 2.50.1-1.fc46 · FEDORA-2026-8c29ba68cc · source
sudo dnf upgrade --advisory=FEDORA-2026-8c29ba68cc
Ubuntu 22.04 · apache-log4j2 · NOT AFFECTED
Ubuntu 20.04 · apache-log4j2 · NOT AFFECTED
Ubuntu 24.04 · apache-log4j2 · NOT AFFECTED
Ubuntu 24.10 · apache-log4j2 · NOT AFFECTED
Ubuntu 25.04 · apache-log4j2 · NOT AFFECTED
Debian 12 · apache-log4j2 · FIXED · 2.7-2
sudo apt update && sudo apt install --only-upgrade apache-log4j2
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' apache-log4j2)" ge "2.7-2" && echo PATCHED || echo STILL-VULNERABLE
Debian 13 · apache-log4j2 · FIXED · 2.7-2
sudo apt update && sudo apt install --only-upgrade apache-log4j2
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' apache-log4j2)" ge "2.7-2" && echo PATCHED || echo STILL-VULNERABLE
RHEL 7 · log4j · FIXED · log4j-1.2.17-16.el7_4
sudo dnf upgrade --advisory=RHSA-2017:2423
rpm -q log4j
RHEL 5 · log4j · DEFERRED
RHEL 6 · log4j · DEFERRED
RHEL OpenStack Platform 7 (Kilo) Operational Tools · log4j · NOT AFFECTED
sudo yum update --advisory=ALAS2-2022-1739
sudo yum update --advisory=ALAS-2022-1562
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- GitHub PoC: pimps/CVE-2017-5645 (92 stars)
- GitHub PoC: HynekPetrak/log4shell-finder (39 stars)
- Write-up: www.oracle.com/security-alerts/cpuApr2021.html
- Write-up: www.oracle.com/security-alerts/cpuapr2020.html
- Write-up: www.oracle.com/security-alerts/cpujan2020.html
- Nuclei scan template: Apache Log4j Server - Deserialization Command Execution
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.
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-2017-5645?
log4j: upgrade to 2.8.2; oncommand api services: mitigate or apply the listed mitigation; oncommand insight: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2017-5645 being exploited?
CVE-2017-5645 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-2017-5645 affect?
CVE-2017-5645 affects log4j, oncommand api services, oncommand insight. Severity is critical (CVSS 9.8). In Apache Log4j 2.x before 2.8.2, when using the TCP socket server or UDP socket server to receive serialized log events from another application, a specially crafted binary payload can be sent that, when deserialized, can execute arbitrary
How urgent is CVE-2017-5645?
Priority 77/100. Critical severity; EPSS top 1%: very likely to be exploited; Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action; On your watchlist
Software pages
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