NVD / CVE Program· CNA apache

CVE-2021-4104: Deserialization of untrusted data in JMSAppender in Apache Log4j 1.2

Noroxi assessment

Priority: Plan (action score 54/100)

A ready-made attack module is public (Nuclei); exploiting it takes no special expertise.
Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
Probability of exploitation in the next 30 days: 80.5% (FIRST EPSS); higher than 99.6% of all records.
Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
Fixed version: parfait (AlmaLinux:8) 0.5.4-4.module_el8.5.0+235+62ea7738, 0.5.4-4.module_el8.5.0+2610+de2b8c0b; parfait-examples (AlmaLinux:8) 0.5.4-4.module_el8.5.0+2610+de2b8c0b, 0.5.4-4.module_el8.5.0+235+62ea7738; parfait-javadoc (AlmaLinux:8) 0.5.4-4.module_el8.5.0+2610+de2b8c0b, 0.5.4-4.module_el8.5.0+235+62ea7738.
Mentioned 6 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Add it to your regular patch cycle. Upgrade to parfait (AlmaLinux:8) 0.5.4-4.module_el8.5.0+235+62ea7738, 0.5.4-4.module_el8.5.0+2610+de2b8c0b; parfait-examples (AlmaLinux:8) 0.5.4-4.module_el8.5.0+2610+de2b8c0b, 0.5.4-4.module_el8.5.0+235+62ea7738; parfait-javadoc (AlmaLinux:8) 0.5.4-4.module_el8.5.0+2610+de2b8c0b, 0.5.4-4.module_el8.5.0+235+62ea7738 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

JMSAppender in Log4j 1.2 is vulnerable to deserialization of untrusted data when the attacker has write access to the Log4j configuration. The attacker can provide TopicBindingName and TopicConnectionFactoryBindingName configurations causing JMSAppender to perform JNDI requests that result in remote code execution in a similar fashion to CVE-2021-44228. Note this issue only affects Log4j 1.2 when specifically configured to use JMSAppender, which is not the default. Apache Log4j 1.2 reached end of life in August 2015. Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.

HighCVSS 7.5 · v3.1—Proof of concept Fix available

Published: Dec 14, 2021
Updated: Jun 17, 2026
EPSS: 80.5% · 99th percentile
CWE: CWE-502

Report tools

JSON

Action score

Plan

Add it to your regular patch cycle.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 24 / 30 · 80.5%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
Proof of concept exists, no weaponized module
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
apache	log4j	cpe:2.3:a:apache:log4j
fedoraproject	fedora	cpe:2.3:o:fedoraproject:fedora
redhat	codeready studio	cpe:2.3:a:redhat:codeready_studio
redhat	integration camel k	cpe:2.3:a:redhat:integration_camel_k
redhat	integration camel quarkus	cpe:2.3:a:redhat:integration_camel_quarkus
redhat	jboss a-mq	cpe:2.3:a:redhat:jboss_a-mq
redhat	jboss a-mq streaming	cpe:2.3:a:redhat:jboss_a-mq_streaming
redhat	jboss data grid	cpe:2.3:a:redhat:jboss_data_grid
redhat	jboss data virtualization	cpe:2.3:a:redhat:jboss_data_virtualization
redhat	jboss enterprise application platform	cpe:2.3:a:redhat:jboss_enterprise_application_platform
redhat	jboss fuse	cpe:2.3:a:redhat:jboss_fuse
redhat	jboss fuse service works	cpe:2.3:a:redhat:jboss_fuse_service_works

and 34 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

apache log4j1.2
fedoraproject fedora35
oracle advanced supply chain planning12.1
oracle advanced supply chain planning12.2
oracle business intelligence12.2.1.3.0
oracle business intelligence12.2.1.4.0
oracle business intelligence5.9.0.0.0
oracle business process management suite12.2.1.3.0
oracle business process management suite12.2.1.4.0
oracle communications eagle ftp table base retrieval4.5
oracle communications messaging server8.1
oracle communications network integrity7.3.6
oracle communications offline mediation controllerbefore 12.0.0.4.0
oracle communications offline mediation controller12.0.0.5.0
oracle communications unified inventory management7.3.4
oracle communications unified inventory management7.3.5
oracle communications unified inventory management7.4.1
oracle communications unified inventory management7.4.2
oracle e-business suite cloud manager and cloud backup module2.2.1.1.1
oracle enterprise manager base platform13.4.0.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

Apache Software Foundation Apache Log4j 1.x
- Apache Log4j 1.2 1.2.xaffected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

+96

Same product

apache: all records

Other highest-scoring records for the same primary product.

CVE-2021-44228Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpointsKEV
100Now
CVE-2021-45046Apache Log4j2 Thread Context Message Pattern and Context Lookup Pattern vulnerable to a denial of service attackKEV
96Now
CVE-2017-5645In 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 applic
66This week

Published before and after this one in the same product

← EarlierCVE-2019-17571Dec 20, 2019 · Included in Log4j 1.2 is a SocketServer class that is vulnerable to deserialization of untrusted data which can be exploited to remotely exe
60This week
← EarlierCVE-2020-9488Apr 27, 2020 · Improper validation of certificate with host mismatch in Apache Log4j SMTP appender.
16Monitor
Later →CVE-2021-45105Dec 18, 2021 · Apache Log4j2 does not always protect from infinite recursion in lookup evaluation
53Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
almalinux:parfait	0.5.4-4.module_el8.5.0+235+62ea7738 · AlmaLinux:8	Package registry (OSV)
almalinux:parfait-examples	0.5.4-4.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:parfait-javadoc	0.5.4-4.module_el8.5.0+235+62ea7738 · AlmaLinux:8	Package registry (OSV)
almalinux:pcp-parfait-agent	0.5.4-4.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:si-units	0.6.5-2.module_el8.5.0+235+62ea7738 · AlmaLinux:8	Package registry (OSV)
almalinux:si-units-javadoc	0.6.5-2.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:unit-api	1.0-5.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:unit-api-javadoc	1.0-5.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:uom-lib	1.0.1-6.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:uom-lib-javadoc	1.0.1-6.module_el8.5.0+2610+de2b8c0b · AlmaLinux:8	Package registry (OSV)
almalinux:uom-parent	1.0.3-3.module_el8.5.0+235+62ea7738 · AlmaLinux:8	Package registry (OSV)
almalinux:uom-se	1.0.4-3.module_el8.5.0+235+62ea7738 · AlmaLinux:8	Package registry (OSV)
debian:apache-log4j1.2	1.2.17-11 · Debian:12	Package registry (OSV)
opensuse:kafka	2.1.0-bp153.2.3.1 · openSUSE:Leap 15.3	Package registry (OSV)
opensuse:kafka-kit	2.1.0-bp153.2.3.1 · openSUSE:Leap 15.3	Package registry (OSV)
opensuse:log4j	1.2.17-5.6.1 · openSUSE:Leap 15.3	Package registry (OSV)
opensuse:log4j12	1.2.17-lp152.3.3.2 · openSUSE:Leap 15.2	Package registry (OSV)
opensuse:log4j12-mini	1.2.17-lp152.3.3.2 · openSUSE:Leap 15.2	Package registry (OSV)
red hat:log4j	0:1.2.14-6.5.el6_10 · Red Hat:rhel_els:6	Package registry (OSV)
red hat:log4j-debuginfo	0:1.2.14-6.5.el6_10 · Red Hat:rhel_els:6	Package registry (OSV)
red hat:log4j-javadoc	0:1.2.14-6.5.el6_10 · Red Hat:rhel_els:6	Package registry (OSV)
red hat:log4j-manual	0:1.2.14-6.5.el6_10 · Red Hat:rhel_els:6	Package registry (OSV)
red hat:parfait	0:0.5.4-4.module+el8.4.0+13998+1b70e2b7 · Red Hat:rhel_eus:8.4::appstream	Package registry (OSV)
red hat:parfait-examples	0:0.5.4-4.module+el8.4.0+13998+1b70e2b7 · Red Hat:rhel_eus:8.4::appstream	Package registry (OSV)
red hat:parfait-javadoc	0:0.5.4-4.module+el8.4.0+13998+1b70e2b7 · Red Hat:rhel_eus:8.4::appstream	Package registry (OSV)
red hat:pcp-parfait-agent	0:0.5.4-4.module+el8.4.0+13998+1b70e2b7 · Red Hat:rhel_eus:8.4::appstream	Package registry (OSV)
red hat:rh-maven36-log4j12	0:1.2.17-23.3.el7 · Red Hat:rhel_software_collections:3::el7	Package registry (OSV)
red hat:rh-maven36-log4j12-javadoc	0:1.2.17-23.3.el7 · Red Hat:rhel_software_collections:3::el7	Package registry (OSV)
red hat:si-units	0:0.6.5-2.module+el8+2463+615f6896 · Red Hat:rhel_eus:8.4::appstream	Package registry (OSV)
red hat:si-units-javadoc	0:0.6.5-2.module+el8+2463+615f6896 · Red Hat:rhel_eus:8.4::appstream	Package registry (OSV)

+21

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

Nuclei detection template ×1
Proof-of-concept repository on GitHub ×3

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Nuclei detection template	Nuclei template flexnet-log4j-rce	—
Proof-of-concept repository on GitHub	stars:20	2021-12-14
Proof-of-concept repository on GitHub	stars:0	2022-01-10
Proof-of-concept repository on GitHub	stars:0	2025-07-11

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

First PoCDec 14, 2021same day
PublishedDec 14, 2021
TodayNov 9, 2026+1791 d

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

apache/logging-log4j2PR 608

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-22-0436 · Jun 20, 2022(IBM Güvenlik Bildirimi)
TR-22-0239 · Mar 21, 2022(IBM Güvenlik Bildirimi)
TR-22-0236 · Mar 18, 2022(IBM Güvenlik Bildirimi)
TR-22-0151 · Feb 17, 2022(IBM Güvenlik Bildirimi)
TR-22-0127 · Feb 10, 2022(RedHat Güvenlik Zafiyeti)
TR-22-0113 · Feb 4, 2022(RedHat Güvenlik Güncellemesi)

All national notices →

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
A low-privileged account is enough.
No user action is required.
Special conditions such as timing or configuration are required.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: High
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-502 · Deserialization of Untrusted Data

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

Data received over the network is deserialized into the language’s native object format without verifying its source. Code paths inside the object can be triggered during deserialization.

The bug in code

The whole CWE-502 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

python

1payload = sock.recv(65536)
2job = pickle.loads(payload)

Fixed

python

1payload = sock.recv(65536)
2if not hmac.compare_digest(sign(payload), header_sig):
3    raise PermissionError("invalid signature")
4job = JobSchema.validate(json.loads(payload))

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

Object InjectionCAPEC-586likelihood: Medium · High

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:47 PM UTC

For records you follow, these changes also arrive as notifications. →

References

www.openwall.com/lists/oss-security/2022/01/18/3

Show all references (13 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records

Noroxi analysis

What does it mean in your environment?

We use this product, ask for help

Data sources and verification

CNA: apache

CVE.org (CNA)May 28, 2026, 7:53 PM UTC
CISA ADPMay 28, 2026, 7:53 PM UTC
NVDJun 17, 2026, 12:19 AM UTC
FIRST EPSSNov 8, 2026, 12:00 AM UTC
OSV / GHSANov 9, 2026, 3:18 AM UTC
NucleiNov 9, 2026, 3:18 AM UTC
PoC-in-GitHubNov 9, 2026, 3:18 AM UTC

Each line is when that source was last processed for this record.

Ecosystem	Package	Affected range	Fix
AlmaLinux:8	parfait	before 0.5.4-4.module_el8.5.0+235+62ea7738	0.5.4-4.module_el8.5.0+235+62ea7738
AlmaLinux:8	parfait	before 0.5.4-4.module_el8.5.0+2610+de2b8c0b	0.5.4-4.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	parfait-examples	before 0.5.4-4.module_el8.5.0+2610+de2b8c0b	0.5.4-4.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	parfait-examples	before 0.5.4-4.module_el8.5.0+235+62ea7738	0.5.4-4.module_el8.5.0+235+62ea7738
AlmaLinux:8	parfait-javadoc	before 0.5.4-4.module_el8.5.0+2610+de2b8c0b	0.5.4-4.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	parfait-javadoc	before 0.5.4-4.module_el8.5.0+235+62ea7738	0.5.4-4.module_el8.5.0+235+62ea7738
AlmaLinux:8	pcp-parfait-agent	before 0.5.4-4.module_el8.5.0+235+62ea7738	0.5.4-4.module_el8.5.0+235+62ea7738
AlmaLinux:8	pcp-parfait-agent	before 0.5.4-4.module_el8.5.0+2610+de2b8c0b	0.5.4-4.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	si-units	before 0.6.5-2.module_el8.5.0+2610+de2b8c0b	0.6.5-2.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	si-units	before 0.6.5-2.module_el8.5.0+235+62ea7738	0.6.5-2.module_el8.5.0+235+62ea7738
AlmaLinux:8	si-units-javadoc	before 0.6.5-2.module_el8.5.0+2610+de2b8c0b	0.6.5-2.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	si-units-javadoc	before 0.6.5-2.module_el8.5.0+235+62ea7738	0.6.5-2.module_el8.5.0+235+62ea7738
AlmaLinux:8	unit-api	before 1.0-5.module_el8.5.0+2610+de2b8c0b	1.0-5.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	unit-api	before 1.0-5.module_el8.5.0+235+62ea7738	1.0-5.module_el8.5.0+235+62ea7738
AlmaLinux:8	unit-api-javadoc	before 1.0-5.module_el8.5.0+235+62ea7738	1.0-5.module_el8.5.0+235+62ea7738
AlmaLinux:8	unit-api-javadoc	before 1.0-5.module_el8.5.0+2610+de2b8c0b	1.0-5.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	uom-lib	before 1.0.1-6.module_el8.5.0+235+62ea7738	1.0.1-6.module_el8.5.0+235+62ea7738
AlmaLinux:8	uom-lib	before 1.0.1-6.module_el8.5.0+2610+de2b8c0b	1.0.1-6.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	uom-lib-javadoc	before 1.0.1-6.module_el8.5.0+235+62ea7738	1.0.1-6.module_el8.5.0+235+62ea7738
AlmaLinux:8	uom-lib-javadoc	before 1.0.1-6.module_el8.5.0+2610+de2b8c0b	1.0.1-6.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	uom-parent	before 1.0.3-3.module_el8.5.0+2610+de2b8c0b	1.0.3-3.module_el8.5.0+2610+de2b8c0b
AlmaLinux:8	uom-parent	before 1.0.3-3.module_el8.5.0+235+62ea7738	1.0.3-3.module_el8.5.0+235+62ea7738
AlmaLinux:8	uom-se	before 1.0.4-3.module_el8.5.0+235+62ea7738	1.0.4-3.module_el8.5.0+235+62ea7738
AlmaLinux:8	uom-se	before 1.0.4-3.module_el8.5.0+2610+de2b8c0b	1.0.4-3.module_el8.5.0+2610+de2b8c0b