CVE-2026-107582 (GCVE-0-2026-107582)
Vulnerability from cvelistv5
Published
2026-10-08 11:48
Modified
2026-10-08 14:18
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Summary
Inefficient algorithmic complexity in the REST API (6.3.3 through 6.3.5) and the IMAP PREVIEW response (6.2.22 through 6.3.5) of Progressive Robot hMailServer allows a remote unauthenticated attacker to make the webmail, the administration console and the REST API unavailable by sending a message. To show a snippet of each message in a folder's message list, the server decoded the character entity references of a message that has an HTML part and no text part with a string replacement whose work grew with the square of their number. A received HTML-only message holding a very large number of entity references therefore keeps one of the listener's four worker threads busy for minutes or longer each time the recipient's webmail lists the folder, without the message being opened, so that a few such listings leave the HTTP listener unable to answer anybody. The IMAP PREVIEW response read such text the same way, holding an IMAP thread for each client that asks for the preview of such a message. The flaw is in the server's shared string class, whose replace and remove both ran in quadratic time.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Progressive Robot Ltd | hMailServer |
Version: 6.2.22-pre1 ≤ |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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