CVE-2026-97873Hinoki check available

CPU exhaustion via unbounded legacy PBE iterations

Published Oct 3, 2026 · Updated Oct 3, 2026

Unbounded PBE iteration counts in Bouncy Castle Java before 1.87 and Java LTS before 2.73.14 let attackers exhaust CPU via encrypted keys. The raw JCA provider's PBES1 and PKCS#12 PBE parameter parsers accept untrusted counts, while Cipher, Mac, and SecretKeyFactory derivations run without a count limit. Exploitation requires an application to process an attacker-supplied encrypted key through these provider paths; one small key can occupy a processing thread for an extended period.

CVSS severityUnavailable
Unscored
EPSS probability0.26%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Unbounded PBE iteration counts in Bouncy Castle Java before 1.87 and Java LTS before 2.73.14 let attackers exhaust CPU via encrypted keys. The raw JCA provider's PBES1 and PKCS#12 PBE parameter parsers accept untrusted counts, while Cipher, Mac, and SecretKeyFactory derivations run without a count limit. Exploitation requires an application to process an attacker-supplied encrypted key through these provider paths; one small key can occupy a processing thread for an extended period.

The record

CVE
CVE-2026-97873
Published
Oct 3, 2026
Updated
Oct 3, 2026
Vendor
Legion of the Bouncy Castle Inc.
Product
Bouncy Castle Java
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=0 <1.86

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Legion of the Bouncy Castle Inc. · Bouncy Castle Javaversion=0 <1.86
Legion of the Bouncy Castle Inc. · Bouncy Castle Java LTSversion=2.73.0 <2.73.13

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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