Vulnerability record
CVE-2026-82509
The short answer
CVE-2026-82509 affects vlang v and is rated critical (CVSS 9.1). It is not in CISA's Known Exploited Vulnerabilities catalog.
What it is
V programming language standard library net.http through version 0.5.2 prior to commit 4077484 contains a TLS certificate validation bypass vulnerability that allows on-path attackers to intercept HTTPS traffic by exploiting the default false value of SSLConnectConfig.validate and FetchConfig.validate, which completes TLS handshakes without verifying certificates in both the mbedtls and OpenSSL backends. Attackers can present an expired, self-signed, wrong-hostname, or untrusted-root certificate to successfully complete the handshake via http.get, http.post, or http.fetch, enabling interception or modification of HTTPS traffic unless validate: true is explicitly configured.
Weakness: CWE-295.
Severity
9.1 critical
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/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
Exploited (CISA KEV)
Not listed
CISA lists confirmed exploitation only
EPSS, next 30 days
No score
FIRST scores CVEs within a day of publication
How it can be exploited
- Attack vector
- Network
- Attack complexity
- High
- Attack requirements
- None
- Privileges required
- None
- User interaction
- None
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- None
Affected products
v. NVD's record lists the exact affected versions.
References
Questions
Is CVE-2026-82509 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog as of 2026-11-10.
How do I fix CVE-2026-82509?
Follow the vendor advisory in the references below. NVD lists the affected versions under its configurations.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Received. The description is NVD's text, quoted as published.
Related
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