CVE-2019-20445
CVE-2019-20445 is a critical-severity vulnerability in Netty with a CVSS 3.x base score of 9.1. Its EPSS exploit-prediction score of 13% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-444.
Key facts
- Severity: Critical (CVSS 3.x base score 9.1)
- CVSS v2: 6.4
- EPSS exploit prediction: 13% (96th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-444
- Affected product: Netty
- Published:
- Last modified:
Description
HttpObjectDecoder.java in Netty before 4.1.44 allows a Content-Length header to be accompanied by a second Content-Length header, or by a Transfer-Encoding header.
Frequently asked questions
- What is CVE-2019-20445?
- HttpObjectDecoder.java in Netty before 4.1.44 allows a Content-Length header to be accompanied by a second Content-Length header, or by a Transfer-Encoding header.
- How severe is CVE-2019-20445?
- CVE-2019-20445 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
- Is CVE-2019-20445 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-20445?
- CVE-2019-20445 primarily affects Netty. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-20445?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2019-20445 published?
- CVE-2019-20445 was published on 2020-01-29 and last updated on 2026-06-17.
References
- https://access.redhat.com/errata/RHSA-2020:0497
- https://access.redhat.com/errata/RHSA-2020:0567
- https://access.redhat.com/errata/RHSA-2020:0601
- https://access.redhat.com/errata/RHSA-2020:0605
- https://access.redhat.com/errata/RHSA-2020:0606
- https://access.redhat.com/errata/RHSA-2020:0804
- https://access.redhat.com/errata/RHSA-2020:0805
- https://access.redhat.com/errata/RHSA-2020:0806
- https://access.redhat.com/errata/RHSA-2020:0811
- https://github.com/netty/netty/compare/netty-4.1.43.Final...netty-4.1.44.Final
- https://github.com/netty/netty/issues/9861
- https://lists.apache.org/thread.html/r030beff88aeb6d7a2d6cd21342bd18686153ce6e26a4171d0e035663%40%3Cissues.flume.apache.org%3E
- https://lists.apache.org/thread.html/r1b103833cb5bc8466e24ff0ecc5e75b45a705334ab6a444e64e840a0%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/r1fcccf8bdb3531c28bc9aa605a6a1bea7e68cef6fc12e01faafb2fb5%40%3Cissues.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r205937c85817a911b0c72655c2377e7a2c9322d6ef6ce1b118d34d8d%40%3Cdev.geode.apache.org%3E
- https://lists.apache.org/thread.html/r2f2989b7815d809ff3fda8ce330f553e5f133505afd04ffbc135f35f%40%3Cissues.spark.apache.org%3E
- https://lists.apache.org/thread.html/r310d2ce22304d5298ff87f10134f918c87919b452734f9841d95682d%40%3Ccommits.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r36fcf538b28f2029e8b4f6b9a772f3b107913a78f09b095c5b153a62%40%3Cissues.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r46f93de62b1e199f3f9babb18128681677c53493546f532ed88c359d%40%3Creviews.spark.apache.org%3E
- https://lists.apache.org/thread.html/r4d3f1d3e333d9c2b2f6e6ae8ed8750d4de03410ac294bcd12c7eefa3%40%3Ccommits.cassandra.apache.org%3E
- https://lists.apache.org/thread.html/r4ff40646e9ccce13560458419accdfc227b8b6ca4ead3a8a91decc74%40%3Cissues.flume.apache.org%3E
- https://lists.apache.org/thread.html/r640eb9b3213058a963e18291f903fc1584e577f60035f941e32f760a%40%3Cissues.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r6945f3c346b7af89bbd3526a7c9b705b1e3569070ebcd0964bcedd7d%40%3Cissues.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r70b1ff22ee80e8101805b9a473116dd33265709007d2deb6f8c80bf2%40%3Ccommits.druid.apache.org%3E
- https://lists.apache.org/thread.html/r7790b9d99696d9eddce8a8c96f13bb68460984294ea6fea3800143e4%40%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/r804895eedd72c9ec67898286eb185e04df852b0dd5fe53cf5b6138f9%40%3Cissues.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r81700644754e66ffea465c869cb477de25f8041e21598e8818fc2c45%40%3Cdev.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r819aaeb9944bdcfca438dcc51f05650dc728daf64dfd7d774fc2499b%40%3Ccommits.zookeeper.apache.org%3E
- https://lists.apache.org/thread.html/r832724df393a7ef25ca4c7c2eb83ad2d6c21c74569acda5233f9f1ec%40%3Ccommits.pulsar.apache.org%3E
- https://lists.apache.org/thread.html/r959474dcf7f88565ed89f6252ca5a274419006cb71348f14764b183d%40%3Ccommits.cassandra.apache.org%3E
Affected products (11)
- cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
- cpe:2.3:a:redhat:jboss_amq_clients:2:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.2:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.3:*:*:*:*:*:*:*
- cpe:2.3:a:apache:spark:2.4.7:*:*:*:*:*:*:*
- cpe:2.3:a:apache:spark:2.4.8:*:*:*:*:*:*:*
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