PatchTheCVECVE-2021-37136: The Bzip2 decompression decoder function doesn't allow setting size restrictions on the decompressed output da
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HIGH 7.5REMOTEUPGRADEUPGRADEUPGRADE
CVE-2021-37136 is a high-severity flaw (CVSS 7.5) affecting netty, quarkus, banking apis. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
The Bzip2 decompression decoder function doesn't allow setting size restrictions on the decompressed output data (which affects the allocation size used during decompression). All users of Bzip2Decoder are affected. The malicious input can trigger an OOME and so a DoS attack
Why this priority
- High severity
- EPSS top 7%: very likely to be exploited
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 5.9% (top 7%) |
| CISA exploited list | No |
| Weakness | CWE-400 |
| Published | 2021-10-19 |
| 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
netty netty UPGRADE
Affected: < 4.1.68
Fixed in: 4.1.68
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy netty || rpm -q netty || netty --version
2. UPGRADE to 4.1.68 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade netty
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade netty
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
quarkus quarkus UPGRADE
Affected: < 2.2.4
Fixed in: 2.2.4
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy quarkus || rpm -q quarkus || quarkus --version
2. UPGRADE to 2.2.4 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade quarkus
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade quarkus
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
oracle banking apis UPGRADE
Affected: >= 18.1 and <= 18.3 · 19.1 · 19.2 · 20.1 · 21.1
Fixed in: newer than 18.3
Safe to downgrade to: a release before 18.1
1. Check installed version
apt-cache policy banking-apis || rpm -q banking-apis || banking-apis --version
2. UPGRADE to newer than 18.3 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade banking-apis
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade banking-apis
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 18.1 (Debian / Ubuntu)
apt-cache madison banking-apis
sudo apt install banking-apis=<VERSION_BEFORE_18.1>
sudo apt-mark hold banking-apis
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list banking-apis
sudo dnf downgrade banking-apis-<VERSION_BEFORE_18.1>
sudo dnf versionlock add banking-apis
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.
oracle banking digital experience DOWNGRADE
Affected: 18.1 · 18.2 · 18.3 · 19.1 · 19.2 · 20.1 · 21.1
Fixed in: no fixed release known
Safe to downgrade to: a release before 18.1
1. Check installed version
apt-cache policy banking-digital-experience || rpm -q banking-digital-experience || banking-digital-experience --version
2. No fixed release: DOWNGRADE to a release before 18.1 (Debian / Ubuntu)
apt-cache madison banking-digital-experience
sudo apt install banking-digital-experience=<VERSION_BEFORE_18.1>
sudo apt-mark hold banking-digital-experience
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list banking-digital-experience
sudo dnf downgrade banking-digital-experience-<VERSION_BEFORE_18.1>
sudo dnf versionlock add banking-digital-experience
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.
oracle coherence DOWNGRADE
Affected: 12.2.1.4.0 · 14.1.1.0.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 12.2.1.4.0
1. Check installed version
apt-cache policy coherence || rpm -q coherence || coherence --version
2. No fixed release: DOWNGRADE to a release before 12.2.1.4.0 (Debian / Ubuntu)
apt-cache madison coherence
sudo apt install coherence=<VERSION_BEFORE_12.2.1.4.0>
sudo apt-mark hold coherence
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list coherence
sudo dnf downgrade coherence-<VERSION_BEFORE_12.2.1.4.0>
sudo dnf versionlock add coherence
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.
oracle commerce guided search DOWNGRADE
Affected: 11.3.2
Fixed in: no fixed release known
Safe to downgrade to: a release before 11.3.2
1. Check installed version
apt-cache policy commerce-guided-search || rpm -q commerce-guided-search || commerce-guided-search --version
2. No fixed release: DOWNGRADE to a release before 11.3.2 (Debian / Ubuntu)
apt-cache madison commerce-guided-search
sudo apt install commerce-guided-search=<VERSION_BEFORE_11.3.2>
sudo apt-mark hold commerce-guided-search
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list commerce-guided-search
sudo dnf downgrade commerce-guided-search-<VERSION_BEFORE_11.3.2>
sudo dnf versionlock add commerce-guided-search
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.
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-2021-37136?
netty: upgrade to 4.1.68; quarkus: upgrade to 2.2.4; banking apis: upgrade to newer than 18.3. Exact commands for each OS are on this page.
Is CVE-2021-37136 being exploited?
CVE-2021-37136 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-2021-37136 affect?
CVE-2021-37136 affects netty, quarkus, banking apis. Severity is high (CVSS 7.5). The Bzip2 decompression decoder function doesn't allow setting size restrictions on the decompressed output data (which affects the allocation size used during decompression). All users of Bzip2Decoder are affected. The malicious input can
How urgent is CVE-2021-37136?
Priority 55/100. High severity; EPSS top 7%: very likely to be exploited; Remotely exploitable, no login, no user action
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