CVE-2026-2833: Pingora core Pingora Vulnerable To HTTP Request Vulnerability

CRITICAL
Advisory Identifier: GHSA-xq2h-p299-vjwv
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CWE-444
Published
Advisory Summary

CVE-2026-2833 is a CRITICAL pingora vulnerable to http request vulnerability (CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')) affecting Pingora core libraries in the crates.io ecosystem. The issue involves pingora vulnerable to http request smuggling via premature upgrade. Remediation is available by upgrading affected packages to version 0.8.0.

CVE-2026-2833 at a Glance

CVE Identifier CVE-2026-2833
GHSA Identifier GHSA-xq2h-p299-vjwv
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Affected Product Pingora core
Package Ecosystem crates.io
Published Date
Last Updated

How to Fix CVE-2026-2833

To remediate this vulnerability, upgrade all affected Pingora core dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

pingora-core fixed: 0.8.0 
Upgrade pingora-core to 0.8.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for pingora-core

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-2833, inspect your project dependencies for Pingora core:

inspect dependencies for pingora-core

Analyze the terminal output to locate any version of Pingora core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.8.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling'), where the product acts as an intermediary http agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed http requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. In Pingora core, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact Pingora versions prior to 0.8.0 would immediately forward bytes following a request with an Upgrade header to the backend, without waiting for a 101 Switching Protocols response. This allows an attacker to smuggle requests to the backend and bypass proxy-level security controls. This vulnerability primarily affects standalone Pingora deployments where a Pingora proxy is exposed to external traffic. An attacker could exploit this to bypass proxy-level ACL controls and WAF logic, poison caches and upstream connections, or perform cross-user attacks by hijacking sessions. Note: Cloudflare customers and Cloudflare's CDN infrastructure were not affected by this vulnerability, as ingress proxies in the CDN stack maintain proper HTTP parsing boundaries and do not prematurely switch to upgraded connection forwarding mode. ### Patches Pingora users should upgrade to Pingora v0.8.0 or higher, which fixes this issue by only switching connection modes after receiving a 101 Switching Protocols response from the backend (hash 824bdeefc61e121cc8861de1b35e8e8f39026ecd). Without a 101 response, subsequent bytes continue to be parsed as HTTP requests. ### Workarounds As a workaround, users may return an error on requests with the Upgrade header present in their request filter logic in order to stop processing bytes beyond the request header and disable downstream connection reuse. ### References See [CVE-2026-2833](https://www.cve.org/cverecord?id=CVE-2026-2833) and the [Cloudflare blog post](https://blog.cloudflare.com/pingora-oss-smuggling-vulnerabilities/) for more details. ### Credits Disclosed responsibly by Rajat Raghav (@xclow3n) through the Cloudflare [Bug Bounty Program](https://www.cloudflare.com/disclosure/).

CVE-2026-2833 Affected Pingora core Versions

1 component(s)
Fixed Versions:
0.8.0
Product / Package Ecosystem Affected Versions Fixed Version
pingora-core
 crates.io
< 0.8.0
0.8.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/cloudflare/pingora/security/advisories/GHSA-xq2h-p299-vjwv
NVD — CVE-2026-2833 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-2833
Pingora core Source Repository REPOSITORY
https://github.com/cloudflare/pingora
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2026-0033.html

Frequently Asked Questions

What is CVE-2026-2833?
CVE-2026-2833 is a security vulnerability in Pingora core involving Pingora vulnerable to HTTP Request Smuggling via Premature Upgrade under CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling').
Which Pingora core versions are affected?
Affected versions include releases prior to 0.8.0 across affected packages: pingora-core.
What version fixes CVE-2026-2833?
Upgrading to 0.8.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is pingora-core affected?
Yes, pingora-core is affected in releases prior to 0.8.0. Upgrade your dependency to 0.8.0 or later.
What CWE is associated with CVE-2026-2833?
CVE-2026-2833 is classified under CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') (The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.).
How can I check crates.io dependencies for CVE-2026-2833?
Run the dependency tree command: 'inspect dependencies for pingora-core'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-xq2h-p299-vjwv",
  "modified" : "2026-03-09T20:45:48Z",
  "published" : "2026-03-05T20:55:29Z",
  "aliases" : [ "CVE-2026-2833" ],
  "summary" : "Pingora vulnerable to HTTP Request Smuggling via Premature Upgrade",
  "details" : "### Impact\nPingora versions prior to 0.8.0 would immediately forward bytes following a request with an Upgrade header to the backend, without waiting for a 101 Switching Protocols response. This allows an attacker to smuggle requests to the backend and bypass proxy-level security controls.\n\nThis vulnerability primarily affects standalone Pingora deployments where a Pingora proxy is exposed to external traffic. An attacker could exploit this to bypass proxy-level ACL controls and WAF logic, poison caches and upstream connections, or perform cross-user attacks by hijacking sessions.\n\nNote: Cloudflare customers and Cloudflare's CDN infrastructure were not affected by this vulnerability, as ingress proxies in the CDN stack maintain proper HTTP parsing boundaries and do not prematurely switch to upgraded connection forwarding mode.\n\n### Patches\nPingora users should upgrade to Pingora v0.8.0 or higher, which fixes this issue by only switching connection modes after receiving a 101 Switching Protocols response from the backend (hash 824bdeefc61e121cc8861de1b35e8e8f39026ecd). Without a 101 response, subsequent bytes continue to be parsed as HTTP requests.\n\n### Workarounds\nAs a workaround, users may return an error on requests with the Upgrade header present in their request filter logic in order to stop processing bytes beyond the request header and disable downstream connection reuse.\n\n### References\nSee [CVE-2026-2833](https://www.cve.org/cverecord?id=CVE-2026-2833) and the [Cloudflare blog post](https://blog.cloudflare.com/pingora-oss-smuggling-vulnerabilities/) for more details.\n\n### Credits\nDisclosed responsibly by Rajat Raghav (@xclow3n) through the Cloudflare [Bug Bounty Program](https://www.cloudflare.com/disclosure/).",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "pingora-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.8.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 0.7.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/cloudflare/pingora/security/advisories/GHSA-xq2h-p299-vjwv"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-2833"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/cloudflare/pingora"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2026-0033.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-444" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-05T20:55:29Z",
    "nvd_published_at" : null
  }
}