Description
V through 0.5.2, fixed in commit 85859f0, contains a server-side request forgery (SSRF) bypass vulnerability that allows attackers to circumvent host-based allowlists by exploiting a parser differential between net.urllib and net.http. Attackers can craft a URL containing a backslash in the authority section such that net.urllib.parse() extracts the trusted host for allowlist validation while net.http.get() normalizes the backslash and connects to the internal host, enabling access to internal network services that the allowlist was intended to block.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| vlang | v | ≤ 0.5.2 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | vlang | 0.5.2-2.1 | openSUSE-SU-2026:11480-1 |
Advisories 1
- openSUSE-SU-2026:11480-1 vlang-0.5.2-2.1 on GA media SUSE / openSUSE Security Updates · Aug 10, 2026
References
- Researcher Disclosure technical-description exploit issue-tracking
- Pull Request issue-tracking patch
- Patch Commit patch
- https://www.vulncheck.com/advisories/v-ssrf-bypass-via-parser-differential-in-net-urllib-and-net-http third-party-advisory