CVE-2023-33202

Application denial of service via crafted ASN.1

Published Nov 23, 2023 · Updated Aug 18, 2025

Denial of service in Bouncy Castle for Java before 1.73 allows local users to crash a consuming application via crafted ASN.1 data. The org.bouncycastle.openssl.PEMParser path parses crafted ASN.1 structures until JVM heap exhaustion raises an OutOfMemoryError. Reachability requires a consuming application to parse the malicious PEM file, and the reported consequence is availability loss without data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in Bouncy Castle for Java before 1.73 allows local users to crash a consuming application via crafted ASN.1 data. The org.bouncycastle.openssl.PEMParser path parses crafted ASN.1 structures until JVM heap exhaustion raises an OutOfMemoryError. Reachability requires a consuming application to parse the malicious PEM file, and the reported consequence is availability loss without data disclosure or modification.

The record

CVE
CVE-2023-33202
Published
Nov 23, 2023
Updated
Aug 18, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-400, T1499
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5GitHub Advisory DatabaseCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo