5.3

CVE-2020-26939: bouncycastle fips_java_api Observable Discrepancy

CVSS: 5.3v3.1MediumModified
AliasesUBUNTU-CVE-2020-26939DEBIAN-CVE-2020-26939DLA-2433-1
Published 02-11-2020Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2020-26939 is a medium (CVSS 5.3) Observable Discrepancy vulnerability in bouncycastle fips_java_api. EPSS estimates a 0.92% chance of exploitation in the next 30 days, higher than 59.7% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.92%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 02-11-2020
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

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.

CVSS metrics

6 scores · 5 sources · 2 versions

EPSS trend

Probability

0.92%

Chance of exploitation in the next 30 days

Percentile

60%

Versus all other CVEs

30-day change

0.00 pp

From 0.92% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.92%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard58 products
  • eco-java-gradle-1.11All versions (No fix recorded)
  • eco-java-gradle-2.0All versions (No fix recorded)
  • eco-java-gradle-2.1All versions (No fix recorded)
  • eco-java-gradle-2.10All versions (No fix recorded)
  • eco-java-gradle-2.11All versions (No fix recorded)
Org.bouncycastle8 products
  • bc-fips< 1.0.2
  • bcprov-ext-jdk15on< 1.61
  • bcprov-ext-jdk16< 1.61
  • bcprov-jdk14< 1.61
  • bcprov-jdk15< 1.61
Bouncycastle2 products
Debian1 product
  • bouncycastle< 1.61-1 | < 1.56-1+deb9u3
Ubuntu1 product
  • bouncycastleAll versions (No fix recorded)

5 vendors · 70 products

References

10 links