CyberSecBulletin
CVE-2026-58059NVD status: Analyzed

BC-JAVA: Inefficient Algorithmic Complexity

CVE-2026-58059 is a high-severity inefficient algorithmic complexity vulnerability in BC-JAVA from Legion of the Bouncy Castle, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.85 as the first without the flaw, so updating BC-JAVA to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.49% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update BC-JAVA to 1.85 or a later version.
  2. Update BC-LTS-JAVA to 2.73.12 or a later version.
  3. Update BC-FJA to 1.0.2.7 or 2.0.2 or 2.1.3, whichever matches your release line, or a later version.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Legion of the Bouncy CastleBC-JAVAbefore 1.851.85
Legion of the Bouncy CastleBC-LTS-JAVA2.73.0 up to, but not including, 2.73.122.73.12
Legion of the Bouncy CastleBC-FJA1.0.0 up to, but not including, 1.0.2.7; 2.0.0 up to, but not including, 2.0.2; 2.1.0 up to, but not including, 2.1.31.0.2.7, 2.0.2, 2.1.3
BouncycastleBouncy Castle For Java LTS2.73.11 and earlierNot stated
BouncycastleFips Java API1.0.0 up to, but not including, 1.0.2.7; 2.0.0 up to, but not including, 2.0.2; 2.1.0 up to, but not including, 2.1.31.0.2.7, 2.0.2, 2.1.3

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA
CVSS 3.17.5HighNVD

Official description

In Bouncy Castle for Java before 1.85, Quadratic-time escaping when stringifying X.500 distinguished names. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Inefficient Algorithmic Complexity

An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.

More Inefficient Algorithmic Complexity vulnerabilities (CWE-407)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in BC-JAVA

All BC-JAVA vulnerabilities

Recent Inefficient Algorithmic Complexity vulnerabilities

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