CVE-2020-19498Public exploitNetwork attack vector

Application crash via fraction denominator overflow

Published Jul 21, 2021 · Updated Aug 4, 2024

Division by zero in libheif 1.4.0 allows context-dependent attackers to crash an application by supplying a crafted HEIF file. During HEIF parsing, Box_clap height calculation passes oversized fraction values into Fraction, where denominator overflow produces zero and an integer division raises SIGFPE. The file must be processed by a libheif-consuming application; the demonstrated result is process termination, with no demonstrated confidentiality or integrity impact.

CVSS severity8.8
High
EPSS probability1.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Division by zero in libheif 1.4.0 allows context-dependent attackers to crash an application by supplying a crafted HEIF file. During HEIF parsing, Box_clap height calculation passes oversized fraction values into Fraction, where denominator overflow produces zero and an integer division raises SIGFPE. The file must be processed by a libheif-consuming application; the demonstrated result is process termination, with no demonstrated confidentiality or integrity impact.

The record

CVE
CVE-2020-19498
Published
Jul 21, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 21, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8CanonicalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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