CVE-2026-58059: Legion of the Bouncy Castle BC-JAVA · Inefficient Algorithmic Complexity
Affects Legion of the Bouncy Castle BC-JAVASource CVE Database V5
Not known to be exploited · CVSS 8.7 High : upgrade to 1.85 soon.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers can reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-08-03.
- Patch
- Available – fixed in 1.85, 2.73.12, 2.1.3 +2
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/U:AmberExploitation evidence
Disclosed: evidence found.
CVE published 3 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade BC-JAVA and Legion of the Bouncy Castle Inc./bcprov to 1.85; BC-LTS-JAVA and Legion of the Bouncy Castle Inc./bcprov-lts8on to 2.73.12; BC-FJA and Legion of the Bouncy Castle Inc./bc-fips to 2.1.3, 2.0.2 or 1.0.2.7.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Legion of the Bouncy Castle Inc.BC-JAVA | Affected
| Fixed in
|
| Legion of the Bouncy Castle Inc.BC-LTS-JAVA | Affected
| Fixed in
|
| Legion of the Bouncy Castle Inc.BC-FJA | Affected
| Fixed in
|
| Legion of the Bouncy Castle Inc.BC-FJA | Affected
| Fixed in
|
| Legion of the Bouncy Castle Inc.BC-FJA | Affected
| Fixed in
|
MavenLegion of the Bouncy Castle Inc./bcprovpkg:maven/Legion of the Bouncy Castle Inc./bcprovOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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).