Unlimited login attempts via unenforced checkout CAPTCHA
Published Apr 24, 2026 · Updated Apr 24, 2026
Rate-limit bypass in HostBill through 2025-11-27 allows remote attackers to automate checkout login attempts without valid CAPTCHA responses. The existing-customer checkout handler accepts requests with the CAPTCHA parameter removed or a previously used value and imposes no server-side attempt limit. An unauthenticated attacker must add an item and reach checkout; the flaw enables password guessing against customer accounts, while successful access still requires a correct password.
Summary
What happened
Rate-limit bypass in HostBill through 2025-11-27 allows remote attackers to automate checkout login attempts without valid CAPTCHA responses. The existing-customer checkout handler accepts requests with the CAPTCHA parameter removed or a previously used value and imposes no server-side attempt limit. An unauthenticated attacker must add an item and reach checkout; the flaw enables password guessing against customer accounts, while successful access still requires a correct password.
The record
- CVE
- CVE-2026-31052
- Published
- Apr 24, 2026
- Updated
- Apr 24, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-400, T1110.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 24, 2026CVE publishedPublication date reported by the CVE source.
- Apr 24, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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.
Public exploit references
- HostBill checkout rate-limit bypass reproductionproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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