CVE-2026-12852
CVE-2026-12852 is a high-severity vulnerability in Bouncycastle Bc-java with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-789.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v4: 8.7
- EPSS exploit prediction: 0% (22nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-789
- Affected product: Bouncycastle Bc-java
- Published:
- Last modified:
Description
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
Frequently asked questions
- What is CVE-2026-12852?
- In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
- How severe is CVE-2026-12852?
- CVE-2026-12852 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2026-12852 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-12852?
- CVE-2026-12852 affects Bouncycastle Bc-java. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-12852?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2026-12852 published?
- CVE-2026-12852 was published on 2026-08-03 and last updated on 2026-08-28.
References
- https://github.com/bcgit/bc-java/commit/a747038bb5bbd5e29fb2b7607ab38af1fd8d1790
- https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9012852
Affected products (1)
- cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*
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