CVE-2026-88829 (GCVE-0-2026-88829)

Vulnerability from cvelistv5 – Published: 2026-10-14 10:00 – Updated: 2026-10-14 10:00
VLAI
Title
Busybox: busybox: http request smuggling via pipelined requests in httpd reverse proxy
Summary
A flaw was found in BusyBox httpd's reverse proxy feature. When the proxy is configured to forward requests matching a URL prefix to a backend server, only the first HTTP request on a TCP connection has its path rewritten. An attacker can send a pipelined second request that is relayed verbatim to the backend, bypassing the configured path restrictions. This allows accessing arbitrary paths on the backend server that were not intended to be exposed through the proxy.
Severity
7.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
redhat CNA under the redhat root
CNA scorecard B 81/100 over 1014 records in the last 180 days details
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-88829 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2531343 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Hardened Images     cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Date Public
2026-10-14 08:00
Credits
Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:hummingbird:1"
          ],
          "defaultStatus": "affected",
          "packageName": "busybox",
          "product": "Red Hat Hardened Images",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue."
        }
      ],
      "datePublic": "2026-10-14T08:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "A flaw was found in BusyBox httpd\u0027s reverse proxy feature. When the proxy is configured to forward requests matching a URL prefix to a backend server, only the first HTTP request on a TCP connection has its path rewritten. An attacker can send a pipelined second request that is relayed verbatim to the backend, bypassing the configured path restrictions. This allows accessing arbitrary paths on the backend server that were not intended to be exposed through the proxy."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Moderate"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.2,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-444",
              "description": "Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request/Response Smuggling\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-14T10:00:42.946Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2026-88829"
        },
        {
          "name": "RHBZ#2531343",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531343"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-09-07T00:00:00.000Z",
          "value": "Reported to Red Hat."
        },
        {
          "lang": "en",
          "time": "2026-10-14T08:00:00.000Z",
          "value": "Made public."
        }
      ],
      "title": "Busybox: busybox: http request smuggling via pipelined requests in httpd reverse proxy",
      "workarounds": [
        {
          "lang": "en",
          "value": "Do not use BusyBox httpd P: rules as the sole path-based access control in front of sensitive backends. Remove P: lines if proxying is not required, or place a full reverse proxy (for example nginx or HAProxy) in front of the backend. Recompile with FEATURE_HTTPD_PROXY disabled if the applet is not needed."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-444: Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request/Response Smuggling\u0027)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-88829",
    "datePublished": "2026-10-14T10:00:42.946Z",
    "dateReserved": "2026-09-10T09:42:04.558Z",
    "dateUpdated": "2026-10-14T10:00:42.946Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-88829",
      "date": "2026-10-14",
      "epss": "0.00317",
      "percentile": "0.22949"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                "cpes": [
                  "cpe:/a:redhat:hummingbird:1"
                ],
                "defaultStatus": "affected",
                "packageName": "busybox",
                "product": "Red Hat Hardened Images",
                "vendor": "Red Hat"
              }
            ],
            "source": "secalert@redhat.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "A flaw was found in BusyBox httpd\u0027s reverse proxy feature. When the proxy is configured to forward requests matching a URL prefix to a backend server, only the first HTTP request on a TCP connection has its path rewritten. An attacker can send a pipelined second request that is relayed verbatim to the backend, bypassing the configured path restrictions. This allows accessing arbitrary paths on the backend server that were not intended to be exposed through the proxy."
          }
        ],
        "id": "CVE-2026-88829",
        "lastModified": "2026-10-14T10:17:57.077",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 7.2,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "CHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 2.7,
              "source": "secalert@redhat.com",
              "type": "Primary"
            }
          ]
        },
        "published": "2026-10-14T10:17:57.077",
        "references": [
          {
            "source": "secalert@redhat.com",
            "url": "https://access.redhat.com/security/cve/CVE-2026-88829"
          },
          {
            "source": "secalert@redhat.com",
            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2531343"
          }
        ],
        "sourceIdentifier": "secalert@redhat.com",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-444"
              }
            ],
            "source": "secalert@redhat.com",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-14T12:36:26+00:00",
      "cve": "CVE-2026-88829",
      "id": "CVE-2026-88829",
      "initial_release_date": "2026-10-14T08:00:00+00:00",
      "product_status:known_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "busybox: busybox: HTTP request smuggling via pipelined requests in httpd reverse proxy",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-88829.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.