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CVE.org (no NVD analysis yet)· CNA apache

CVE-2026-87830: Apache WSS4J: Streaming WS-SecurityPolicy validation may skip element-protection checks.

CriticalCVSS 9.1 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 36/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.21% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: Apache Software Foundation Apache WSS4J 2.4.4, 3.0.6, 4.0.2.

Low priority for now. Upgrade to Apache Software Foundation Apache WSS4J 2.4.4, 3.0.6, 4.0.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the StAX streaming WS-SecurityPolicy validator, certain relative or unsupported XPath expressions can be converted into paths that never match the actual XML element path. A remote SOAP peer may therefore send a required element without the expected signature or encryption. Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.

Published
Sep 30, 2026
Updated
Oct 6, 2026
EPSS
0.2% · 12th percentile

Report tools

JSON

Action score

36

Monitor

Low priority for now.

CVSS
36 / 40 · 9.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-87830

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
apachewss4j

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

  • Apache Software Foundation Apache WSS4J

    • 4.0.0 and later · before 4.0.2affected · semver
    • 3.0.0 and later · before 3.0.6affected · semver
    • before 2.4.4affected · semver

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apache wss4jbefore 2.4.4
  • apache wss4j3.0.0 and later · before 3.0.6
  • apache wss4j4.0.0 and later · before 4.0.2

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:13wss4jfrom 0—

Same product

apache: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-88920Apache WSS4J: SAML Sender-Vouches Authentication Bypass
    39Monitor
  • CVE-2026-89238Apache WSS4J: WSS4J EncryptedHeader child confusion causing wrong protected-header selection
    36Monitor
  • CVE-2015-0226Apache WSS4J before 1.6.17 and 2.0.x before 2.0.2 improperly leaks information about decryption failures when decrypting an encrypted key…
    32Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2015-0227Feb 12, 2015 · Apache WSS4J before 1.6.17 and 2.x before 2.0.2 allows remote attackers to bypass the requireSignedEncryptedDataElements configuration via…
    22Monitor
  • ← EarlierCVE-2026-85532Sep 30, 2026 · Apache WSS4J: Insufficient Validation of Derived-Key Parameters
    30Monitor
  • Later →CVE-2026-92121Sep 30, 2026 · Apache WSS4J: WS-SecurityPolicy signature checks skipped in the streaming code after an STR-Transform reference
    30Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Apache Software Foundation Apache WSS4J2.4.4Vendor (CNA)
Apache Software Foundation Apache WSS4J3.0.6Vendor (CNA)
Apache Software Foundation Apache WSS4J4.0.2Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. Fix recordedsame day
  3. TodayNov 12, 2026+43 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Not on record for this CVE: patch commit or PR link · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
None

Weakness class (CWE)

CWE-917 · Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. CVSS— → 9.1
  2. Severity— → critical
  3. SSVC exploitation— → none
  4. Exploit maturity— → none
  5. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records