CVE-2026-59646
published 2026-08-03CVE-2026-59646: In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length. This issue also affects Bouncy Castle for Java…
PriorityP341high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.35%
28.3th percentile
In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bctls-fips 1.0.24 (1.0.X series), 2.0.24 (2.0.X series) and 2.1.24 (2.1.X series).
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| bouncycastle | bc-java | < 1.85 | 1.85 |
| bouncycastle | bctls-fips | < 1.0.24 | 1.0.24 |
| bouncycastle | bctls-fips | >= 2.0.19 < 2.0.24 | 2.0.24 |
| bouncycastle | bctls-fips | >= 2.1.20 < 2.1.24 | 2.1.24 |
| bouncycastle | bouncy_castle_for_java_lts | <= 2.73.11 | — |
| legion_of_the_bouncy_castle_inc | bc-fja | >= 1.0.0 < 1.0.24 | 1.0.24 |
| legion_of_the_bouncy_castle_inc | bc-fja | >= 2.0.0 < 2.0.24 | 2.0.24 |
| legion_of_the_bouncy_castle_inc | bc-fja | >= 2.1.0 < 2.1.24 | 2.1.24 |
| legion_of_the_bouncy_castle_inc | bc-java | < 1.85 | 1.85 |
| legion_of_the_bouncy_castle_inc | bc-lts-java | >= 2.73.0 < 2.73.12 | 2.73.12 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber
vendor_redhat8.7HIGH
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VulDB
Legion of the Bouncy Castle Bouncy Castle for Java DTLS Handshake Reassembler buffer overflow
vuldb·2026-08-03·CVSS 8.7
CVE-2026-59646 [HIGH] Legion of the Bouncy Castle Bouncy Castle for Java DTLS Handshake Reassembler buffer overflow
A vulnerability labeled as critical has been found in Legion of the Bouncy Castle Bouncy Castle for Java, Bouncy Castle for Java LTS and Bouncy Castle for Java FIPS. Affected by this issue is some unknown functionality of the component DTLS Handshake Reassembler. Such manipulation leads to buffer overflow.
This vulnerability is referenced as CVE-2026-59646. It is possible to launch the attack remotely. No exploit is available.
GHSA
In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length.
ghsa_unreviewed·2026-08-03
CVE-2026-59646 [HIGH] CWE-789 In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length.
In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bctls-fips 1.0.24 (1.0.X series), 2.0.24 (2.0.X series) and 2.1.24 (2.1.X series).
Red Hat
org.bouncycastle/bc-java: org.bouncycastle/bctls-fips: Bouncy Castle for Java: Denial of Service via unchecked DTLS handshake reassembler buffer allocation
vendor_redhat·2026-08-03·CVSS 8.7
CVE-2026-59646 [HIGH] CWE-131 org.bouncycastle/bc-java: org.bouncycastle/bctls-fips: Bouncy Castle for Java: Denial of Service via unchecked DTLS handshake reassembler buffer allocation
org.bouncycastle/bc-java: org.bouncycastle/bctls-fips: Bouncy Castle for Java: Denial of Service via unchecked DTLS handshake reassembler buffer allocation
In Bouncy Castle for Java before 1.85, DTLS handshake reassembler allocates buffer from unchecked 24-bit length. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bctls-fips 1.0.24 (1.0.X series), 2.0.24 (2.0.X series) and 2.1.24 (2.1.X series).
A flaw was found in Bouncy Castle for Java. The DTLS (Datagram Transport Layer Security) handshake reassembler allocates buffers based on an unchecked 24-bit length value. A remote attacker could exploit this vulnerability by sending a specially crafted DTLS handshake message, leading to excessive memory allocation and a denial o
No detection rules found.
No public exploits indexed.
2026-08-03
Published