CVE-2026-56764: Hono - Timing Attack in basicAuth and bearerAuth Middleware
Vulnerability summary
CVE-2026-56764 is a medium (CVSS 6.3) Observable Timing Discrepancy vulnerability in hono. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 22.4% of scored vulnerabilities.
Not severe (CVSS 6.3, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 2Timeline
- 15-07-2026PublishedVulnerability first disclosed.
- 15-07-2026Last modifiedVulnerability information updated.
Description
Hono before 4.11.10 contains a timing attack vulnerability in the basicAuth and bearerAuth middlewares due to non-constant-time string comparison in the timingSafeEqual function. Attackers can exploit early termination of string equality checks to infer valid credentials through precise timing measurements.
CVSS metrics
6 scores · 4 sources · 2 versions- OSV · ChainguardEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
- NVDNIST6.3MediumCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · NpmEcosystem advisory · calculated3.7LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
- NVDNIST3.7LowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS trend
Probability
0.30%
Chance of exploitation in the next 30 days
Percentile
22%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.30% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Chainguard7 products
- honoAll versions (No fix recorded)
- hono-adapter-mqttAll versions (No fix recorded)
- hono-cliAll versions (No fix recorded)
- hono-compatAll versions (No fix recorded)
- hono-service-authAll versions (No fix recorded)
Hono1 product
- hono< 4.11.10
Npm1 product
- hono< 4.11.10
3 vendors · 9 products
References
7 links- www.vulncheck.com/advisories/hono-timing-attack-in-basicauth-and-bearerauth-middlewareThird Party AdvisoryAdvisory
- github.com/honojs/honoPACKAGE
