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5.3
MEDIUM CVSS 3.1
CVE-2020-26939
Bouncy Castle RSA OAEPEncoding Private Exponent Information Leak
Description

In Legion of the Bouncy Castle BC before 1.61 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEncoding. Sending invalid ciphertext that decrypts to a short payload in the OAEP Decoder could result in the throwing of an early exception, potentially leaking some information about the private exponent of the RSA private key performing the encryption.

INFO

Published Date :

Nov. 2, 2020, 10:15 p.m.

Last Modified :

July 17, 2025, 5:04 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2020-26939 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Bouncycastle fips_java_api
2 Bouncycastle legion-of-the-bouncy-castle-fips-java-api
3 Bouncycastle legion-of-the-bouncy-castle
4 Bouncycastle bouncy_castle_for_java
: Total Affected Vendor : 1 | Products : 4
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 MEDIUM [email protected]
CVSS 3.1 MEDIUM [email protected]
Solution
This information is provided by the 3rd party feeds.
  • Upgrade the affected packages.
Public PoC/Exploit Available at Github

CVE-2020-26939 has a 6 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2020-26939.

URL Resource
https://github.com/bcgit/bc-java/wiki/CVE-2020-26939 Patch Third Party Advisory
https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e%40%3Cissues.solr.apache.org%3E
https://github.com/bcgit/bc-java/wiki/CVE-2020-26939 Patch Third Party Advisory
https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e%40%3Cissues.solr.apache.org%3E
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2020-26939 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2020-26939 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Profile Photo
CGCL-codes/LibHunter

None

Python Shell Batchfile

Updated: 1 month, 4 weeks ago
3 stars 1 fork 1 watcher
Born at : Sept. 14, 2024, 5:56 a.m. This repo has been linked 90 different CVEs too.
Profile Photo
LibHunter/LibHunter

None

Python Shell Batchfile

Updated: 1 year, 2 months ago
0 stars 0 fork 0 watcher
Born at : June 5, 2024, 8:22 a.m. This repo has been linked 90 different CVEs too.
Profile Photo
CGCL-codes/PHunter

None

Java

Updated: 11 months ago
8 stars 3 fork 3 watcher
Born at : May 27, 2023, 11:55 a.m. This repo has been linked 90 different CVEs too.
Profile Photo
Anonymous-Phunter/PHunter

None

Java

Updated: 2 months, 3 weeks ago
3 stars 2 fork 2 watcher
Born at : Nov. 14, 2022, 2:30 a.m. This repo has been linked 90 different CVEs too.
Profile Photo
pctF/vulnerable-app

Vulnerable dummy-application for checking different SCA tools

Updated: 4 years, 7 months ago
0 stars 1 fork 1 watcher
Born at : Dec. 26, 2020, 9:05 p.m. This repo has been linked 48 different CVEs too.
Profile Photo
box/box-java-sdk

The Box SDK for Java.

hacktoberfest

Java Rich Text Format

Updated: 1 week, 6 days ago
159 stars 185 fork 185 watcher
Born at : Oct. 24, 2014, 9:39 p.m. This repo has been linked 2 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2020-26939 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2020-26939 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CPE Deprecation Remap by [email protected]

    Jul. 17, 2025

    Action Type Old Value New Value
    Changed CPE Configuration OR *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle-fips-java-api:*:*:*:*:*:*:*:* versions from (excluding) 1.0.1.2 OR *cpe:2.3:a:bouncycastle:fips_java_api:*:*:*:*:*:*:*:* versions from (excluding) 1.0.1.2
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://github.com/bcgit/bc-java/wiki/CVE-2020-26939
    Added Reference https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e%40%3Cissues.solr.apache.org%3E
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference MITRE https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e%40%3Cissues.solr.apache.org%3E [No types assigned]
    Removed Reference MITRE https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e@%3Cissues.solr.apache.org%3E
  • Reanalysis by [email protected]

    May. 28, 2021

    Action Type Old Value New Value
    Removed CPE Configuration OR *cpe:2.3:a:apache:solr:8.8.2:*:*:*:*:*:*:*
  • Modified Analysis by [email protected]

    May. 26, 2021

    Action Type Old Value New Value
    Changed Reference Type https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e@%3Cissues.solr.apache.org%3E No Types Assigned https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e@%3Cissues.solr.apache.org%3E Mailing List, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:apache:solr:8.8.2:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    May. 25, 2021

    Action Type Old Value New Value
    Added Reference https://lists.apache.org/thread.html/r8c36ba34e80e05eecb1f80071cc834d705616f315b634ec0c7d8f42e@%3Cissues.solr.apache.org%3E [No Types Assigned]
  • Modified Analysis by [email protected]

    Dec. 23, 2020

    Action Type Old Value New Value
    Removed CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
    Changed CPE Configuration OR *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle:*:*:*:*:*:*:*:* versions up to (excluding) 1.55 *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle-fips-java-api:*:*:*:*:*:*:*:* versions up to (excluding) 1.0.1.2 OR *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle:*:*:*:*:*:*:*:* versions up to (excluding) 1.61 *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle-fips-java-api:*:*:*:*:*:*:*:* versions up to (excluding) 1.0.1.2
  • CVE Modified by [email protected]

    Dec. 21, 2020

    Action Type Old Value New Value
    Changed Description In Legion of the Bouncy Castle BC before 1.55 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEncoding. Sending invalid ciphertext that decrypts to a short payload in the OAEP Decoder could result in the throwing of an early exception, potentially leaking some information about the private exponent of the RSA private key performing the encryption. In Legion of the Bouncy Castle BC before 1.61 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEncoding. Sending invalid ciphertext that decrypts to a short payload in the OAEP Decoder could result in the throwing of an early exception, potentially leaking some information about the private exponent of the RSA private key performing the encryption.
    Removed Reference https://github.com/bcgit/bc-java/commit/930f8b274c4f1f3a46e68b5441f1e7fadb57e8c1 [Patch, Third Party Advisory]
    Removed Reference https://lists.debian.org/debian-lts-announce/2020/11/msg00007.html [Mailing List, Third Party Advisory]
    Removed Reference https://security.netapp.com/advisory/ntap-20201202-0005/ [No Types Assigned]
  • CVE Modified by [email protected]

    Dec. 02, 2020

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20201202-0005/ [No Types Assigned]
  • Initial Analysis by [email protected]

    Nov. 17, 2020

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:N/A:N)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
    Changed Reference Type https://github.com/bcgit/bc-java/commit/930f8b274c4f1f3a46e68b5441f1e7fadb57e8c1 No Types Assigned https://github.com/bcgit/bc-java/commit/930f8b274c4f1f3a46e68b5441f1e7fadb57e8c1 Patch, Third Party Advisory
    Changed Reference Type https://github.com/bcgit/bc-java/wiki/CVE-2020-26939 No Types Assigned https://github.com/bcgit/bc-java/wiki/CVE-2020-26939 Patch, Third Party Advisory
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2020/11/msg00007.html No Types Assigned https://lists.debian.org/debian-lts-announce/2020/11/msg00007.html Mailing List, Third Party Advisory
    Added CWE NIST CWE-203
    Added CPE Configuration OR *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle:*:*:*:*:*:*:*:* versions up to (excluding) 1.55 *cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle-fips-java-api:*:*:*:*:*:*:*:* versions up to (excluding) 1.0.1.2
    Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Nov. 05, 2020

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2020/11/msg00007.html [No Types Assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 5.3
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 5
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

2.35 }} 1.59%

score

0.84267

percentile