Denial of service via super-linear MIME parsing
Published Sep 24, 2026 · Updated Sep 24, 2026
Denial of service in ZBateson MailMimeParser 2.0.0 through 3.0.5 and 4.0.0 through 4.0.1 allows remote attackers to exhaust resources via crafted MIME. Multipart nesting, header-count and header-size paths perform super-linear work, and sibling appends scale quadratically when getAllParts() or content access triggers lazy parsing. Any application that parses attacker-controlled email is exposed; a small message can consume seconds of CPU or gigabytes of memory and cause an out-of-memory kill.
Summary
What happened
Denial of service in ZBateson MailMimeParser 2.0.0 through 3.0.5 and 4.0.0 through 4.0.1 allows remote attackers to exhaust resources via crafted MIME. Multipart nesting, header-count and header-size paths perform super-linear work, and sibling appends scale quadratically when getAllParts() or content access triggers lazy parsing. Any application that parses attacker-controlled email is exposed; a small message can consume seconds of CPU or gigabytes of memory and cause an out-of-memory kill.
The record
- CVE
- CVE-2026-61816
- Published
- Sep 24, 2026
- Updated
- Sep 24, 2026
- Vendor
- ZBateson
- Product
- MailMimeParser
- Classifications
- CWE-400, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 24, 2026CVE publishedPublication date reported by the CVE source.
- Sep 24, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 2.0.0, < 3.0.6
- Affected versionversion=>= 4.0.0, < 4.0.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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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.
Public exploit references
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Technologies
Your stack
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Your stack
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