CVE-2026-33129— h3 has an observable timing discrepancy in basic auth utils
Quick assessment
Affected
h3js h3
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
H3是H3开源的一个HTTP框架。 H3 2.0.1-beta.0至2.0.0-rc.8版本存在安全漏洞，该漏洞源于requireBasicAuth函数使用不安全的字符串比较，可能导致时序侧信道攻击。
Possible ATT&CK Techniques 1 AI
T1212 · Exploitation for Credential Access
Get alerts for future matching vulnerabilities
Log in to subscribe
I. Basic Information for CVE-2026-33129
Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗
Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.
Vulnerability Title
h3 has an observable timing discrepancy in basic auth utils
Source: CVE Program / CVE List V5
Vulnerability Description
H3 is a minimal H(TTP) framework. Versions 2.0.1-beta.0 through 2.0.0-rc.8 contain a Timing Side-Channel vulnerability in the requireBasicAuth function due to the use of unsafe string comparison (!==). This allows an attacker to deduce the valid password character-by-character by measuring the server's response time, effectively bypassing password complexity protections. This issue is fixed in version 2.0.1-rc.9.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
通过时间差异性导致的信息暴露
Source: CVE Program / CVE List V5
Vulnerability Title
H3 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
H3是H3开源的一个HTTP框架。 H3 2.0.1-beta.0至2.0.0-rc.8版本存在安全漏洞，该漏洞源于requireBasicAuth函数使用不安全的字符串比较，可能导致时序侧信道攻击。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2026-33129
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POC
Premium
No public POC found.
Login to generate AI POCIII. Intelligence Information for CVE-2026-33129
请登录查看更多情报信息。
Patches & Fixes for CVE-2026-33129 (2)
-
Release v2.0.1-rc.9 · h3js/h3 · GitHub x_refsource_MISC
Vendor Advisories for CVE-2026-33129 (1)
-
observable timing discrepancy in basic auth utils · Advisory · h3js/h3 · GitHub x_refsource_CONFIRM
Same Patch Batch · h3js · 2026-03-20 · 3 CVEs total
| CVE-2026-33128 | 7.5 HIGH | h3 has a Server-Sent Events Injection via Unsanitized Newlines in Event Stream Fields |
| CVE-2026-33131 | 7.4 HIGH | h3 has a middleware bypass with one gadget |
IV. Related Vulnerabilities
Same vendor: h3js
-
CVE-2026-33732
srvx is vulnerable to middleware bypass via absolute URI in -
CVE-2026-33490
h3: Missing Path Segment Boundary Check in `mount()` Causes -
CVE-2026-33131
h3 has a middleware bypass with one gadget -
CVE-2026-33128
h3 has a Server-Sent Events Injection via Unsanitized Newlin -
CVE-2026-23527
h3 v1 has Request Smuggling (TE.TE) issue
Same weakness: CWE-208
-
CVE-2026-80199
Kimai before 2.54.0 Username Enumeration via Timing Oracle -
CVE-2026-18259
Token Content Access - Moderately critical - Access bypass - -
CVE-2026-72701
Grav CMS before 2.0.16 Timing Attack via verifyNonce -
CVE-2026-72700
Grav before 3.9.1 Timing Attack via Non-Constant-Time Token -
CVE-2026-53525
WeeChat has Non-Constant-Time Password Hash Comparison in Re
V. Comments for CVE-2026-33129
No comments yet