CVE-2026-12852
published 2026-08-03CVE-2026-12852: In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.31%
23.5th percentile
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| bouncycastle | bc-java | < 1.85 | 1.85 |
| legion_of_the_bouncy_castle_inc | bc-java | >= 1.73 < 1.85 | 1.85 |
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
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
ghsa_unreviewed·2026-08-03
CVE-2026-12852 [HIGH] CWE-789 In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
Red Hat
bouncycastle: Bouncy Castle for Java: Denial of Service via MLS wire decoder
vendor_redhat·2026-08-03·CVSS 8.7
CVE-2026-12852 [HIGH] CWE-1284 bouncycastle: Bouncy Castle for Java: Denial of Service via MLS wire decoder
bouncycastle: Bouncy Castle for Java: Denial of Service via MLS wire decoder
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
A flaw was found in Bouncy Castle for Java. A remote attacker could exploit this by providing a specially crafted message to the MLS wire decoder. The decoder allocates an attacker-declared opaque length without first performing a bounds check. This can lead to excessive memory allocation, resulting in a Denial of Service (DoS) for the application.
Statement: This vulnerability targets the Messaging Layer Security (MLS) module, which in Bouncy Castle is packaged as bcmls. No Red Hat products are affected.
Package: bcpkix-jdk18on (Cryostat 4) - Not affected
Package: bcprov-jdk18on (Cryostat 4)
No detection rules found.
No public exploits indexed.
2026-08-03
Published