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Fencer Intel
medium 6.1

CVE-2025-46721 json

nosurf vulnerable to CSRF due to non-functional same-origin request checks

published last yr. modified 4mo ago also EUVD-2025-14655 , GHSA-w9hf-35q4-vcjw , GO-2025-3683

cvss
6.1
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits
0
none known

Summary

nosurf is cross-site request forgery (CSRF) protection middleware for Go. A vulnerability in versions prior to 1.2.0 allows an attacker who controls content on the target site, or on a subdomain of the target site (either via XSS, or otherwise) to bypass CSRF checks and issue requests on user's behalf. Due to misuse of the Go `net/http` library, nosurf categorizes all incoming requests as plain-text HTTP requests, in which case the `Referer` header is not checked to have the same origin as the target webpage. If the attacker has control over HTML contents on either the target website (e.g. `example.com`), or on a website hosted on a subdomain of the target (e.g. `attacker.example.com`), they will also be able to manipulate cookies set for the target website. By acquiring the secret CSRF token from the cookie, or overriding the cookie with a new token known to the attacker, `attacker.example.com` is able to craft cross-site requests to `example.com`. A patch for the issue was released in nosurf 1.2.0. In lieu of upgrading to a patched version of nosurf, users may additionally use another HTTP middleware to ensure that a non-safe HTTP request is coming from the same origin (e.g. by requiring a `Sec-Fetch-Site: same-origin` header in the request).

Patch / fix

  • go github.com/justinas/nosurf 1.2.0
  • nosurf_project nosurf 1.2.0
  • govulncheck-vulndb openSUSE Tumbleweed 0.0.20250515T200012-1.1

opensuse advisories openSUSE-SU-2025:15135-1

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/advisories/GHSA-rq77-p4h8-4crw referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/justinas/nosurf-cve-2025-46721 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CNA 4.0 6.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/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
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
go github.com/justinas/nosurf
<1.2.0
1.2.0

Affected products

  • justinas nosurf

Classification

Weakness
  • CWE-352 Cross-Site Request Forgery

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.