How severe is CVE-2026-45045?

CVE-2026-45045 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-45045 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45045?

CVE-2026-45045 affects Gofiber Fiber. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-45045?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-45045 published?

CVE-2026-45045 was published on 2026-07-08 and last updated on 2026-07-15.

CVE-2026-45045

CVE-2026-45045 is a medium-severity vulnerability in Gofiber Fiber with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-290.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-290
Affected product: Gofiber Fiber
Published: 2026-07-08
Last modified: 2026-07-15

Description

Fiber is an Express inspired web framework written in Go. Prior to 3.3.0 and 2.52.14, the BalancerForward proxy helper in middleware/proxy/proxy.go uses Header.Add() instead of Header.Set() when injecting X-Real-IP, allowing an attacker-supplied first X-Real-IP value to be forwarded to upstream servers for logging, rate limiting, and access control. This issue is fixed in version 3.3.0 and 2.52.14.

Frequently asked questions

What is CVE-2026-45045?: Fiber is an Express inspired web framework written in Go. Prior to 3.3.0 and 2.52.14, the BalancerForward proxy helper in middleware/proxy/proxy.go uses Header.Add() instead of Header.Set() when injecting X-Real-IP, allowing an attacker-supplied first X-Real-IP value to be forwarded to upstream servers for logging, rate limiting, and access control. This issue is fixed in version 3.3.0 and 2.52.14.
How severe is CVE-2026-45045?: CVE-2026-45045 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-45045 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45045?: CVE-2026-45045 affects Gofiber Fiber. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45045?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-45045 published?: CVE-2026-45045 was published on 2026-07-08 and last updated on 2026-07-15.

References

Affected products (1)

cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*

More vulnerabilities in Gofiber Fiber

CVE-2024-38513 — Critical (CVSS 10.0): Fiber is an Express-inspired web framework written in Go A vulnerability present in versions prior to 2.52.5 is a…
CVE-2023-45128 — Critical (CVSS 10.0): Fiber is an express inspired web framework written in Go. A Cross-Site Request Forgery (CSRF) vulnerability has been…
CVE-2025-66630 — Critical (CVSS 9.4): Fiber is an Express inspired web framework written in Go. Before 2.52.11, on Go versions prior to 1.24, the underlying…
CVE-2024-25124 — Critical (CVSS 9.4): Fiber is a web framework written in go. Prior to version 2.52.1, the CORS middleware allows for insecure configurations…
CVE-2023-45141 — High (CVSS 8.6): Fiber is an express inspired web framework written in Go. A Cross-Site Request Forgery (CSRF) vulnerability has been…
CVE-2026-25899 — High (CVSS 7.5): Fiber is an Express inspired web framework written in Go. In versions on the v3 branch prior to 3.1.0, the use of the…

All CVEs affecting Gofiber Fiber →

Other CWE-290 vulnerabilities

CVE-2026-54782 — Critical (CVSS 10.0): CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1,…
CVE-2026-48567 — Critical (CVSS 10.0): Authentication bypass by spoofing in Azure HorizonDB allows an unauthorized attacker to elevate privileges over a…
CVE-2026-6213 — Critical (CVSS 10.0): A vulnerability in Remote Spark SparkView before build 1122 allows an attacker to bypasses the local connection check…
CVE-2026-39858 — Critical (CVSS 10.0): Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a high…
CVE-2025-66570 — Critical (CVSS 10.0): cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability…
CVE-2025-34063 — Critical (CVSS 10.0): A cryptographic authentication bypass vulnerability exists in OneLogin AD Connector prior to 6.1.5 due to the exposure…

Browse all CWE-290 vulnerabilities →