Skip to content
VulniPulse
Sign in
Highest advisory severityMedium 2 vendors · 2 advisories

CVE-2026-63317

Apache OpenNLP: Arbitrary Class Instantiation

CVE-2026-63317: Apache OpenNLP: Arbitrary Class Instantiation. Not in the CISA KEV catalog. Medium advisory severity (CVSS 5.8, Red Hat).

Compare the source-linked records below. Ratings and product/version details belong to each advisory; they are not a single CVE-wide score or proof that every listed product is affected. How VulniPulse collects and checks evidence.

NVD detail CVE.org

Get an email when Apache publishes the next one.

VulniPulse checks Apache's security advisories around the clock and emails you new ones with the severity, the fixed version and the vendor's link. First month free, then US$15/month; we email you before the first charge.

Start your free month

CVE-2026-63317 key facts

CISA KEV
Not listed (catalog checked )
Highest advisory severity
Medium
CVSS base score
5.8 (Red Hat), 5.6 (Apache)
Fixed releases
  • Apache: 2.5.10, 3.0.0-M5
Vendor advisories
2 from Apache, Red Hat
VulniPulse record
Published · Updated

Scores, vectors, weaknesses and fixed releases are quoted from vendor advisories that cover only CVE-2026-63317; bulletin-wide values are not repeated here.

Is CVE-2026-63317 exploited?

No exploitation is reported in the sources VulniPulse tracks: CVE-2026-63317 is not in the CISA KEV catalog (checked ) and no tracked advisory for it reports exploitation. That is not proof the vulnerability cannot be exploited.

How do I fix CVE-2026-63317?

Upgrade to a fixed release named by the vendor:

  • Apache: 2.5.10, 3.0.0-M5
  • T Mitigation: Upgrade to a fixed release. (Apache)
  • Users who cannot upgrade immediately should ensure all model files and format names are sourced from trusted origins and should audit their classpath for classes with side-effecting static initializers or constructors. (Apache)

Vendor advisory comparison

Apache

1 advisory
  • Advisory severityMedium5.6

    Medium [CVE-2026-63317] Apache OpenNLP: Arbitrary Class Instantiation

    CVE-2026-63317Source published Source updated

    Arbitrary Class Instantiation via XML Feature Generator Descriptor and Format Name in Apache OpenNLP Versions Affected: - before 2.5.10 - before 3.0.0-M5 Description: Three code paths in Apache OpenNLP load a class by its fully-qualified name via Class.forName() and invoke its no-arg constructor without any prior validation of the class name or its type. The affected paths are: (1) GeneratorFactory, which reads the class attribute of generator elements in an XML feature generator descriptor; such descriptors are embedded as artifacts in model archives (e.g. TokenNameFinder and POSTagger models) and are parsed during model loading, so an attacker who can supply a crafted model archive controls the class name directly. (2) StreamFactoryRegistry.getFactory(Class, String), which falls back…

    Affected products in this advisory
    • Apache OpenNLP
    Source-reported affected versions
    • 2.5.10
    • 3.0.0
    Source-reported fixed versions
    • 2.5.10
    • 3.0.0-M5
    Mitigation guidance
    • T Mitigation: Upgrade to a fixed release.
    • Users who cannot upgrade immediately should ensure all model files and format names are sourced from trusted origins and should audit their classpath for classes with side-effecting static initializers or constructors.
    Full advisory and evidenceOpen source bulletin

Red Hat

1 advisory
  • Advisory severityMedium5.8

    Medium [CVE-2026-63317] Arbitrary class instantiation via crafted XML or untrusted format names

    CVE-2026-63317Source published Source updated

    Arbitrary Class Instantiation via XML Feature Generator Descriptor and Format Name in Apache OpenNLP Versions Affected: - before 2.5.10 - before 3.0.0-M5 Description: Three code paths in Apache OpenNLP load a class by its fully-qualified name via Class.forName() and invoke its no-arg constructor without any prior validation of the class name or its type. The affected paths are: (1) GeneratorFactory, which reads the class attribute of generator elements in an XML feature generator descriptor; such descriptors are embedded as artifacts in model archives (e.g. TokenNameFinder and POSTagger models) and are parsed during model loading, so an attacker who can supply a crafted model archive controls the class name directly. (2) StreamFactoryRegistry.getFactory(Class, String), which falls back…

    Affected products in this advisory
    • Red Hat JBoss Enterprise Application Platform Expansion Pack
    Source-reported affected versions
    • < 2.5.10
    • < 3.0.0-M5
    • 3.0.0
    Source-reported fixed versions
    No fixed-version detail extracted. This does not mean no fix exists.
    Mitigation guidance
    No mitigation guidance extracted; consult the source.
    Full advisory and evidenceOpen source bulletin

More Apache advisories

All Apache advisories

Follow CVE-2026-63317 in the free weekly digest

Every Monday: whether it was added to CISA KEV, reported exploited, got a fix or changed severity, plus the week's critical and high advisories.

Free, no account. Confirm by email; unsubscribe in one click. Choose vendors and severity

Browse the latest tracked CVEs or the CVEs listed in CISA KEV.

Android app · Google Play

Get alerts for new CVEs on your phone.

Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 34 official vendor sources and 160+ reviewed platform categories.

Matching phone alertsOptional email delivery
Get CVE alertsSee app features