Description
BouncyCastle TLS prior to version 1.0.3, when configured to use the JCE (Java Cryptography Extension) for cryptographic functions, provides a weak Bleichenbacher oracle when any TLS cipher suite using RSA key exchange is negotiated. An attacker can recover the private key from a vulnerable application. This vulnerability is referred to as "ROBOT."
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Legion of the Bouncy Castle | BouncyCastle TLS | <1.0.3 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | bouncycastle | 1.58-1 | — |
| Debian 13 | bouncycastle | 1.58-1 | — |
| Debian 12 | bouncycastle | 1.58-1 | — |
| Debian 9 | bouncycastle | 1.56-1+deb9u1 | DSA-4072-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | bouncycastle | 1.68-3.2 | openSUSE-SU-2024:10661-1 |
| openSUSE Leap 15.1 | bouncycastle | 1.60-lp151.3.3.1 | openSUSE-SU-2020:0607-1 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Metasploit 1 module
-
Scanner for Bleichenbacher Oracle in RSA PKCS #1 v1.5
auxiliary/scanner/ssl/bleichenbacher_oracle
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.bouncycastle:bcprov-jdk15on | < 1.0.3 | 1.0.3 | GHSA-wrwf-pmmj-w989 |
Advisories 3
- DSA-4072-1 bouncycastle - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10661-1 bouncycastle-1.68-3.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0607-1 Security update for bouncycastle SUSE / openSUSE Security Updates · Feb 4, 2026
References
- 102195 vdb-entry
- VU#144389 third-party-advisory
- DSA-4072 vendor-advisory
- openSUSE-SU-2020:0607 vendor-advisory
- https://www.oracle.com/security-alerts/cpuoct2020.html
- https://robotattack.org/
- https://github.com/bcgit/bc-java/commit/a00b684465b38d722ca9a3543b8af8568e6bad5c
- https://security.netapp.com/advisory/ntap-20171222-0001/