Vulnerability-Lookup

WID-SEC-W-2026-2012

Vulnerability from csaf_certbund - Published: 2026-06-18 22:00 - Updated: 2026-07-20 22:00

Summary

HAProxy: Mehrere Schwachstellen

Severity

Hoch

Notes

Das BSI ist als Anbieter für die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch dafür verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgfältig im Einzelfall zu prüfen.

Produktbeschreibung: HAProxy ist ein weit verbreiteter Open Source Software Load Balancer und Application Delivery Controller.

Angriff: Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in HAProxy ausnutzen, um Dateien zu manipulieren oder einen Denial of Service zu verursachen.

Betroffene Betriebssysteme: - Linux - UNIX

CVE-2026-55203

Affected products

Known affected 3 products

Product	Identifier	Version
SUSE Linux SUSE	`cpe:/o:suse:suse_linux:-`	—
Red Hat Enterprise Linux Red Hat	`cpe:/o:redhat:enterprise_linux:-`	—
HAProxy HAProxy 3.4.0 commit <5985276 HAProxy / HAProxy		3.4.0 commit <5985276

CVE-2026-55204

Affected products

Known affected 3 products

Product	Identifier	Version
SUSE Linux SUSE	`cpe:/o:suse:suse_linux:-`	—
Red Hat Enterprise Linux Red Hat	`cpe:/o:redhat:enterprise_linux:-`	—
HAProxy HAProxy 3.4.0 <commit 9a6d1fe HAProxy / HAProxy		3.4.0 <commit 9a6d1fe

References

12 references

URL	Category
https://wid.cert-bund.de/.well-known/csaf/white/2…	self
https://wid.cert-bund.de/portal/wid/securityadvis…	self
https://github.com/advisories/GHSA-58MJ-CMHG-35RG	external
https://github.com/advisories/GHSA-4VJ2-5MVX-3VCC	external
https://lists.suse.com/pipermail/sle-security-upd…	external
https://lists.suse.com/pipermail/sle-security-upd…	external
https://lists.suse.com/pipermail/sle-security-upd…	external
https://lists.suse.com/pipermail/sle-security-upd…	external
https://lists.suse.com/pipermail/sle-security-upd…	external
https://lists.suse.com/pipermail/sle-security-upd…	external
https://access.redhat.com/errata/RHSA-2026:35453	external
https://lists.suse.com/pipermail/sle-security-upd…	external

JSON

To clipboard

{
  "document": {
    "aggregate_severity": {
      "text": "hoch"
    },
    "category": "csaf_base",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "de-DE",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
      },
      {
        "category": "description",
        "text": "HAProxy ist ein weit verbreiteter Open Source Software Load Balancer und Application Delivery Controller.",
        "title": "Produktbeschreibung"
      },
      {
        "category": "summary",
        "text": "Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in HAProxy ausnutzen, um Dateien zu manipulieren oder einen Denial of Service zu verursachen.",
        "title": "Angriff"
      },
      {
        "category": "general",
        "text": "- Linux\n- UNIX",
        "title": "Betroffene Betriebssysteme"
      }
    ],
    "publisher": {
      "category": "other",
      "contact_details": "csaf-provider@cert-bund.de",
      "name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
      "namespace": "https://www.bsi.bund.de"
    },
    "references": [
      {
        "category": "self",
        "summary": "WID-SEC-W-2026-2012 - CSAF Version",
        "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2012.json"
      },
      {
        "category": "self",
        "summary": "WID-SEC-2026-2012 - Portal Version",
        "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2012"
      },
      {
        "category": "external",
        "summary": "GitHub Advisory Database vom 2026-06-18",
        "url": "https://github.com/advisories/GHSA-58MJ-CMHG-35RG"
      },
      {
        "category": "external",
        "summary": "GitHub Advisory Database vom 2026-06-18",
        "url": "https://github.com/advisories/GHSA-4VJ2-5MVX-3VCC"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:2651-1 vom 2026-06-26",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-June/027030.html"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:2652-1 vom 2026-06-26",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-June/027029.html"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:22515-1 vom 2026-07-08",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-July/027313.html"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:22544-1 vom 2026-07-13",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-July/027398.html"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:22557-1 vom 2026-07-14",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-July/027452.html"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:22587-1 vom 2026-07-14",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-July/027436.html"
      },
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        "category": "external",
        "summary": "Red Hat Security Advisory RHSA-2026:35453 vom 2026-07-16",
        "url": "https://access.redhat.com/errata/RHSA-2026:35453"
      },
      {
        "category": "external",
        "summary": "SUSE Security Update SUSE-SU-2026:22663-1 vom 2026-07-20",
        "url": "https://lists.suse.com/pipermail/sle-security-updates/2026-July/027662.html"
      }
    ],
    "source_lang": "en-US",
    "title": "HAProxy: Mehrere Schwachstellen",
    "tracking": {
      "current_release_date": "2026-07-20T22:00:00.000+00:00",
      "generator": {
        "date": "2026-07-21T06:48:12.714+00:00",
        "engine": {
          "name": "BSI-WID",
          "version": "1.6.0"
        }
      },
      "id": "WID-SEC-W-2026-2012",
      "initial_release_date": "2026-06-18T22:00:00.000+00:00",
      "revision_history": [
        {
          "date": "2026-06-18T22:00:00.000+00:00",
          "number": "1",
          "summary": "Initiale Fassung"
        },
        {
          "date": "2026-06-28T22:00:00.000+00:00",
          "number": "2",
          "summary": "Neue Updates von SUSE aufgenommen"
        },
        {
          "date": "2026-07-08T22:00:00.000+00:00",
          "number": "3",
          "summary": "Neue Updates von SUSE aufgenommen"
        },
        {
          "date": "2026-07-13T22:00:00.000+00:00",
          "number": "4",
          "summary": "Neue Updates von SUSE aufgenommen"
        },
        {
          "date": "2026-07-14T22:00:00.000+00:00",
          "number": "5",
          "summary": "Neue Updates von SUSE aufgenommen"
        },
        {
          "date": "2026-07-16T22:00:00.000+00:00",
          "number": "6",
          "summary": "Neue Updates von Red Hat aufgenommen"
        },
        {
          "date": "2026-07-20T22:00:00.000+00:00",
          "number": "7",
          "summary": "Neue Updates von SUSE aufgenommen"
        }
      ],
      "status": "final",
      "version": "7"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "3.4.0 commit \u003c5985276",
                "product": {
                  "name": "HAProxy HAProxy 3.4.0 commit \u003c5985276",
                  "product_id": "T055637"
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              },
              {
                "category": "product_version",
                "name": "3.4.0 commit 5985276",
                "product": {
                  "name": "HAProxy HAProxy 3.4.0 commit 5985276",
                  "product_id": "T055637-fixed",
                  "product_identification_helper": {
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                }
              },
              {
                "category": "product_version_range",
                "name": "3.4.0 \u003ccommit 9a6d1fe",
                "product": {
                  "name": "HAProxy HAProxy 3.4.0 \u003ccommit 9a6d1fe",
                  "product_id": "T055638"
                }
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                "product": {
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        "category": "vendor",
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        "branches": [
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            "category": "product_name",
            "name": "Red Hat Enterprise Linux",
            "product": {
              "name": "Red Hat Enterprise Linux",
              "product_id": "67646",
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                "cpe": "cpe:/o:redhat:enterprise_linux:-"
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            "category": "product_name",
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                "cpe": "cpe:/o:suse:suse_linux:-"
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      "product_status": {
        "known_affected": [
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      },
      "release_date": "2026-06-18T22:00:00.000+00:00",
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      "release_date": "2026-06-18T22:00:00.000+00:00",
      "title": "CVE-2026-55204"
    }
  ]
}

CVE-2026-55203 (GCVE-0-2026-55203)

Vulnerability from cvelistv5 – Published: 2026-06-18 16:05 – Updated: 2026-07-14 21:33 X_Open Source

Title

HAProxy - Integer Overflow in FCGI Demux Record Length Field

Summary

HAProxy through 3.4.0, fixed in commit 5985276, contains an integer overflow vulnerability in the fcgi_conn structure's drl field that allows buffer misparse as new FCGI record headers. When contentLength is 65535 and paddingLength is 1 or more, the drl field wraps to 0, causing incorrect record consumption and allowing malicious FastCGI backends to desynchronize the FCGI framing parser, potentially causing request routing errors, response smuggling, or memory safety issues.

Severity

9 (Critical)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/SA:N

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-23 02:04 UTC

CWE

CWE-190 - Integer Overflow or Wraparound

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/haproxy/haproxy/commit/5985276…	patch
https://www.vulncheck.com/advisories/haproxy-inte…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
haproxy	haproxy	Affected: 0 , ≤ 3.4.0 (semver) Unaffected: 5985276735777634d8c85f1d73bb7764aab0d6dd (git) cpe:2.3:a:haproxy:aloha::::::::

Date Public

2026-06-16 00:00

Credits

Tristan Madani (@TristanInSec)

Show details on NVD website

JSON

To clipboard

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CVE-2026-55204 (GCVE-0-2026-55204)

Vulnerability from cvelistv5 – Published: 2026-06-18 16:05 – Updated: 2026-07-14 21:33 X_Open Source

Title

HAProxy - NULL Pointer Dereference in hpack_dht_insert Function

Summary

HAProxy through 3.4.0, fixed in commit 9a6d1fe, contains a null pointer dereference vulnerability in hpack_dht_insert() within src/hpack-tbl.c that fails to validate the return value of hpack_dht_defrag() when the memory pool is exhausted. An attacker can trigger HPACK dynamic table insertions under memory pressure to dereference a NULL pointer and crash HAProxy worker processes, causing denial of service.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-18 17:26 UTC

CWE

CWE-476 - NULL Pointer Dereference

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/haproxy/haproxy/commit/9a6d1fe…	patch
https://www.vulncheck.com/advisories/haproxy-null…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
haproxy	haproxy	Affected: 0 , ≤ 3.4.0 (semver) Unaffected: 9a6d1fe3f00d86ab4ea6ea6ea0a5d48fc058a513 (git) cpe:2.3:a:haproxy:aloha::::::::

Date Public

2026-06-16 00:00

Credits

Tristan Madani (@TristanInSec)

Show details on NVD website

JSON

To clipboard

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                  "criteria": "cpe:2.3:a:haproxy:aloha:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "3.4.0",
                  "vulnerable": true
                }
              ],
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Tristan Madani (@TristanInSec)"
        }
      ],
      "datePublic": "2026-06-16T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "HAProxy through  3.4.0, fixed in commit 9a6d1fe, contains a null pointer dereference vulnerability in hpack_dht_insert() within src/hpack-tbl.c that fails to validate the return value of hpack_dht_defrag() when the memory pool is exhausted. An attacker can trigger HPACK dynamic table insertions under memory pressure to dereference a NULL pointer and crash HAProxy worker processes, causing denial of service."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-476",
              "description": "NULL Pointer Dereference",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-14T21:33:57.879Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "Patch Commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/haproxy/haproxy/commit/9a6d1fe3f00d86ab4ea6ea6ea0a5d48fc058a513"
        },
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/haproxy-null-pointer-dereference-in-hpack-dht-insert-function"
        }
      ],
      "tags": [
        "x_open-source"
      ],
      "title": "HAProxy - NULL Pointer Dereference in hpack_dht_insert Function",
      "x_generator": {
        "engine": "vulncheck"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-55204",
    "datePublished": "2026-06-18T16:05:52.058Z",
    "dateReserved": "2026-06-16T15:53:37.765Z",
    "dateUpdated": "2026-07-14T21:33:57.879Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

WID-SEC-W-2026-2012

CVE-2026-55203 (GCVE-0-2026-55203)

CVE-2026-55204 (GCVE-0-2026-55204)

Tags

Sightings

Nomenclature