GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

RHSA-2026:55448

Vulnerability from csaf_opensuse - Published: 2026-08-17 00:00 - Updated: 2026-09-16 18:44
Summary
security update for libXfont2
Severity
Important
Notes
Title of the patch: security update for libXfont2
Description of the patch: This security update provides a functional equivalent of RHSA-2026:55448. The original Red Hat(R) advisory is available from the Red Hat web site at https://access.redhat.com/errata/RHSA-2026:55448.
Patchnames: RHSA-2026:55448
Terms of use: CSAF 2.0 data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0).
CVE-2026-44950
9 (Critical)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Affected products
Product Identifier Version Remediation
Unresolved product id: SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64 —
Vendor Fix
Unresolved product id: SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64 —
Vendor Fix
Threats
Impact critical
CVE-2026-59679
9 (Critical)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Affected products
Recommended 2 products, the same list as for CVE-2026-44950
Threats
Impact critical
References
To clipboard 

{
  "document": {
    "aggregate_severity": {
      "namespace": "https://www.suse.com/support/security/rating/",
      "text": "Important"
    },
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Copyright 2024 SUSE LLC. All rights reserved.",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "summary",
        "text": "security update for libXfont2",
        "title": "Title of the patch"
      },
      {
        "category": "description",
        "text": "This security update provides a functional equivalent of RHSA-2026:55448.\nThe original Red Hat(R) advisory is available from the Red Hat web site at\nhttps://access.redhat.com/errata/RHSA-2026:55448.\n",
        "title": "Description of the patch"
      },
      {
        "category": "details",
        "text": "RHSA-2026:55448",
        "title": "Patchnames"
      },
      {
        "category": "legal_disclaimer",
        "text": "CSAF 2.0 data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0).",
        "title": "Terms of use"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "https://www.suse.com/support/security/contact/",
      "name": "SUSE Product Security Team",
      "namespace": "https://www.suse.com/"
    },
    "references": [
      {
        "category": "external",
        "summary": "SUSE ratings",
        "url": "https://www.suse.com/support/security/rating/"
      },
      {
        "category": "self",
        "summary": "URL of this CSAF notice",
        "url": "https://ftp.suse.com/pub/projects/security/csaf/rhsa-2026_55448.json"
      },
      {
        "category": "self",
        "summary": "URL for RHSA-2026:55448",
        "url": "https://lists.suse.com/pipermail/suse-liberty-linux-updates/2026-August/007455.html"
      },
      {
        "category": "self",
        "summary": "E-Mail link for RHSA-2026:55448",
        "url": "https://lists.suse.com/pipermail/suse-liberty-linux-updates/2026-August/007455.html"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-44950 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-44950/"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-59679 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-59679/"
      }
    ],
    "title": "security update for libXfont2",
    "tracking": {
      "current_release_date": "2026-09-16T18:44:31Z",
      "generator": {
        "date": "2026-08-17T00:00:00Z",
        "engine": {
          "name": "cve-database.git:bin/generate-csaf.pl",
          "version": "1"
        }
      },
      "id": "RHSA-2026:55448",
      "initial_release_date": "2026-08-17T00:00:00Z",
      "revision_history": [
        {
          "date": "2026-08-17T00:00:00Z",
          "number": "1",
          "summary": "Current version"
        },
        {
          "date": "2026-09-16T18:02:29Z",
          "number": "2",
          "summary": "unknown changes"
        },
        {
          "date": "2026-09-16T18:44:31Z",
          "number": "3",
          "summary": "unknown changes"
        }
      ],
      "status": "final",
      "version": "3"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "libXfont2-2.0.6-5.el10_2.3.x86_64",
                "product": {
                  "name": "libXfont2-2.0.6-5.el10_2.3.x86_64",
                  "product_id": "libXfont2-2.0.6-5.el10_2.3.x86_64",
                  "product_identification_helper": {
                    "cpe": "cpe:2.3:a:x:libxfont:2.0.6:*:*:*:*:*:*:*",
                    "purl": "pkg:rpm/suse/libXfont2@2.0.6-5.el10_2.3?arch=x86_64"
                  }
                }
              },
              {
                "category": "product_version",
                "name": "libXfont2-devel-2.0.6-5.el10_2.3.x86_64",
                "product": {
                  "name": "libXfont2-devel-2.0.6-5.el10_2.3.x86_64",
                  "product_id": "libXfont2-devel-2.0.6-5.el10_2.3.x86_64",
                  "product_identification_helper": {
                    "cpe": "cpe:2.3:a:x:libxfont:2.0.6:*:*:*:*:*:*:*",
                    "purl": "pkg:rpm/suse/libXfont2-devel@2.0.6-5.el10_2.3?arch=x86_64\u0026upstream=libXfont2-2.0.6-5.el10_2.3.src.rpm"
                  }
                }
              }
            ],
            "category": "architecture",
            "name": "x86_64"
          },
          {
            "branches": [
              {
                "category": "product_name",
                "name": "SUSE Liberty Linux 10",
                "product": {
                  "name": "SUSE Liberty Linux 10",
                  "product_id": "SUSE Liberty Linux 10",
                  "product_identification_helper": {
                    "cpe": "cpe:/o:suse:sll:10"
                  }
                }
              }
            ],
            "category": "product_family",
            "name": "SUSE Linux Enterprise"
          }
        ],
        "category": "vendor",
        "name": "SUSE"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "libXfont2-2.0.6-5.el10_2.3.x86_64 as component of SUSE Liberty Linux 10",
          "product_id": "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64"
        },
        "product_reference": "libXfont2-2.0.6-5.el10_2.3.x86_64",
        "relates_to_product_reference": "SUSE Liberty Linux 10"
      },
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "libXfont2-devel-2.0.6-5.el10_2.3.x86_64 as component of SUSE Liberty Linux 10",
          "product_id": "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
        },
        "product_reference": "libXfont2-devel-2.0.6-5.el10_2.3.x86_64",
        "relates_to_product_reference": "SUSE Liberty Linux 10"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-44950",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-44950"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) copies each glyph\u0027s bitmap into a single buffer. Existing checks validates only that the source slice (position, length) lies within the source bitmap buffer. It does not check whether the running destination cursor has exceeded the allocation.\n\nA malicious font server can send overlapping source offsets -- for example 1000 glyphs each referencing {position:0, length:64} with nbytes=64. Each individual source range passes the existing validation, but the cumulative writes total 64000 bytes into a 64-byte destination buffer. This is a heap buffer overflow with attacker-controlled content.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64",
          "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-44950",
          "url": "https://www.suse.com/security/cve/CVE-2026-44950"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1268514 for CVE-2026-44950",
          "url": "https://bugzilla.suse.com/1268514"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1272661 for CVE-2026-44950",
          "url": "https://bugzilla.suse.com/1272661"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64",
            "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 9,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64",
            "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-08-17T00:00:00Z",
          "details": "critical"
        }
      ],
      "title": "CVE-2026-44950"
    },
    {
      "cve": "CVE-2026-59679",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-59679"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "fs_read_glyphs() in the libXfont2 font-server client (src/fc/fserve.c) indexes the per-character encoding[] array using num_chars from the FS_QueryXBitmaps16 reply, but that array was allocated with a size derived from num_extents in the separate FS_QueryXExtents16 reply. The two CARD32 fields are never cross-checked.\nA malicious or compromised font server can send a small num_extents (e.g. 1) in the extents reply, then a large num_chars (e.g. 100000) in the bitmaps reply. This causes attacker-controlled out-of-bounds heap read and writes.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64",
          "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-59679",
          "url": "https://www.suse.com/security/cve/CVE-2026-59679"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1272660 for CVE-2026-59679",
          "url": "https://bugzilla.suse.com/1272660"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64",
            "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 9,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "SUSE Liberty Linux 10:libXfont2-2.0.6-5.el10_2.3.x86_64",
            "SUSE Liberty Linux 10:libXfont2-devel-2.0.6-5.el10_2.3.x86_64"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-08-17T00:00:00Z",
          "details": "critical"
        }
      ],
      "title": "CVE-2026-59679"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.


Detection rules are retrieved from Rulezet.


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.