5.3
MEDIUM
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 :

Nov. 21, 2024, 5:20 a.m.

Remotely Exploitable :

Yes !

Impact Score :

1.4

Exploitability Score :

3.9
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.

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 legion-of-the-bouncy-castle-fips-java-api
2 Bouncycastle legion-of-the-bouncy-castle
3 Bouncycastle bouncy_castle_for_java
References to Advisories, Solutions, and Tools

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).

None

Python Shell Batchfile

Updated: 1 month, 1 week ago
0 stars 0 fork 0 watcher
Born at : Sept. 14, 2024, 5:56 a.m. This repo has been linked 90 different CVEs too.

None

Python Shell Batchfile

Updated: 6 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.

None

Java

Updated: 2 months, 3 weeks 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.

None

Java

Updated: 1 year, 3 months ago
3 stars 1 fork 1 watcher
Born at : Nov. 14, 2022, 2:30 a.m. This repo has been linked 90 different CVEs too.

Vulnerable dummy-application for checking different SCA tools

Updated: 3 years, 11 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.

The Box SDK for Java.

hacktoberfest

Java Rich Text Format

Updated: 1 week, 5 days ago
157 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.

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.

  • 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.
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.

Exploit Prediction

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

0.07 }} -0.01%

score

0.33011

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability