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.
Source :
[email protected]
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.
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.
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
None
Python Shell Batchfile
None
Java
None
Java
Vulnerable dummy-application for checking different SCA tools
The Box SDK for Java.
hacktoberfest
Java Rich Text Format
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.
-
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]
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.
0.76 }} -0.19%
score
0.72263
percentile