CVE-2026-72587: CoreBunch Instatic · HTTP Request/Response Smuggling
Affects CoreBunch InstaticSource CVE Database V5
Not known to be exploited · CVSS 6.1 Medium : upgrade to 0.0.15 when convenient.
Data as of 7 Nov 2026, 23:24 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.0.15
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 8 Nov 2026.
What to do
Upgrade corebunch/Instatic to 0.0.15.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| CoreBunchInstatic | Affected
| Fixed in– |
GitHubcorebunch/Instaticpkg:github/corebunch/InstaticOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, users should consider restricting access to the vulnerable endpoint or implementing additional input validation and cache controls as temporary mitigations.
Description
CVE-2026-72587 is a medium severity cache poisoning vulnerability in CoreBunch's Instatic product versions prior to 0.0.15. It allows an unauthenticated remote attacker to manipulate the shared process-wide render cache by exploiting the u query parameter in a specific GET request endpoint. This vulnerability is related to inconsistent interpretation of HTTP requests, categorized under CWE-444 (HTTP Request/Response Smuggling).