How severe is CVE-2016-1000338?

CVE-2016-1000338 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 high, and availability none.

Is CVE-2016-1000338 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-1000338?

CVE-2016-1000338 primarily affects Bouncycastle Legion-of-the-bouncy-castle-java-crytography-api. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-1000338?

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-2016-1000338 published?

CVE-2016-1000338 was published on 2018-06-01 and last updated on 2026-06-17.

CVE-2016-1000338

CVE-2016-1000338 is a high-severity vulnerability in Bouncycastle Legion-of-the-bouncy-castle-java-crytography-api 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-347.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Bouncycastle Legion-of-the-bouncy-castle-java-crytography-api
Published: 2018-06-01
Last modified: 2026-06-17

Description

In Bouncy Castle JCE Provider version 1.55 and earlier the DSA does not fully validate ASN.1 encoding of signature on verification. It is possible to inject extra elements in the sequence making up the signature and still have it validate, which in some cases may allow the introduction of 'invisible' data into a signed structure.

Frequently asked questions

What is CVE-2016-1000338?: In Bouncy Castle JCE Provider version 1.55 and earlier the DSA does not fully validate ASN.1 encoding of signature on verification. It is possible to inject extra elements in the sequence making up the signature and still have it validate, which in some cases may allow the introduction of 'invisible' data into a signed structure.
How severe is CVE-2016-1000338?: CVE-2016-1000338 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 high, and availability none.
Is CVE-2016-1000338 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-1000338?: CVE-2016-1000338 primarily affects Bouncycastle Legion-of-the-bouncy-castle-java-crytography-api. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-1000338?: 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-2016-1000338 published?: CVE-2016-1000338 was published on 2018-06-01 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:bouncycastle:legion-of-the-bouncy-castle-java-crytography-api:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:satellite:6.4:-:*:*:*:*:*:*
cpe:2.3:a:redhat:satellite_capsule:6.4:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:*:*:*:*
cpe:2.3:a:netapp:7-mode_transition_tool:-:*:*:*:*:*:*:*

Other CWE-347 (Improper Verification of Cryptographic Signature) vulnerabilities

CVE-2026-48558 — Critical (CVSS 10.0): SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions contain an authentication bypass vulnerability in the…
CVE-2023-25574 — Critical (CVSS 10.0): `jupyterhub-ltiauthenticator` is a JupyterHub authenticator for learning tools interoperability (LTI).…
CVE-2024-45409 — Critical (CVSS 10.0): The Ruby SAML library is for implementing the client side of a SAML authorization. Ruby-SAML in <= 12.2 and 1.13.0 <=…
CVE-2024-32962 — Critical (CVSS 10.0): xml-crypto is an xml digital signature and encryption library for Node.js. In affected versions the default…
CVE-2022-24884 — Critical (CVSS 10.0): ecdsautils is a tiny collection of programs used for ECDSA (keygen, sign, verify). `ecdsa_verify_[prepare_]legacy()`…
CVE-2021-33885 — Critical (CVSS 10.0): An Insufficient Verification of Data Authenticity vulnerability in B. Braun SpaceCom2 prior to 012U000062 allows a…

Browse all CWE-347 (Improper Verification of Cryptographic Signature) vulnerabilities →