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

CVE-2026-84450 (GCVE-0-2026-84450)

Vulnerability from cvelistv5 – Published: 2026-09-18 16:04 – Updated: 2026-09-18 16:04
VLAI
Title
libheif: `clap` + oversized `ispe` aborts on an assert in `Fraction::Fraction` (incomplete fix for CVE-2026-62289)
Summary
libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
strukturag libheif Affected: >= 1.19.0, < 1.23.3
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "libheif",
          "vendor": "strukturag",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 1.19.0, \u003c 1.23.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 4.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-617",
              "description": "CWE-617: Reachable Assertion",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-18T16:04:54.422Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/strukturag/libheif/security/advisories/GHSA-gh5q-69gg-c964",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/strukturag/libheif/security/advisories/GHSA-gh5q-69gg-c964"
        },
        {
          "name": "https://github.com/strukturag/libheif/commit/1c2df9c0e814f89716f3a4d85a444b2dbc63ad69",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/strukturag/libheif/commit/1c2df9c0e814f89716f3a4d85a444b2dbc63ad69"
        },
        {
          "name": "https://github.com/strukturag/libheif/releases/tag/v1.23.3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/strukturag/libheif/releases/tag/v1.23.3"
        }
      ],
      "source": {
        "advisory": "GHSA-gh5q-69gg-c964",
        "discovery": "UNKNOWN"
      },
      "title": "libheif: `clap` + oversized `ispe` aborts on an assert in `Fraction::Fraction` (incomplete fix for CVE-2026-62289)"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-84450",
    "datePublished": "2026-09-18T16:04:54.422Z",
    "dateReserved": "2026-09-01T20:05:09.423Z",
    "dateUpdated": "2026-09-18T16:04:54.422Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "libheif",
                "vendor": "strukturag",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003e= 1.19.0, \u003c 1.23.3"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.3, a crafted image item containing a clap property and an ispe width or height greater than INT32_MAX + 1 can reach crop calculations through heif_image_handle_get_image_tiling(). Box_clap::left_rounded() or Box_clap::top_rounded() passes the image dimension minus one to Fraction::Fraction(), whose uint32_t constructor uses an assertion as input validation, causing assert-enabled builds to abort. Release builds can instead compute invalid crop geometry, and the tiling API returns dimensions that the normal decode security limits reject. This issue is fixed in version 1.23.3."
          }
        ],
        "id": "CVE-2026-84450",
        "lastModified": "2026-09-18T16:17:13.283",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "LOW",
                "baseScore": 4.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "REQUIRED",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 1.4,
              "source": "security-advisories@github.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-09-18T16:17:13.160",
        "references": [
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/strukturag/libheif/commit/1c2df9c0e814f89716f3a4d85a444b2dbc63ad69"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/strukturag/libheif/releases/tag/v1.23.3"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/strukturag/libheif/security/advisories/GHSA-gh5q-69gg-c964"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-617"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Primary"
          }
        ]
      }
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-18T00:25:05Z",
      "cve": "CVE-2026-84450",
      "id": "CVE-2026-84450",
      "initial_release_date": "2026-09-10T16:26:34Z",
      "product_status:first_fixed": "23",
      "product_status:known_affected": "69",
      "product_status:known_not_affected": "27",
      "product_status:recommended": "12",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-84450",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-84450.json",
      "version": "4"
    }
  }
}



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.