CVE-2021-26927Public exploit

Application crash via unchecked JP2 component mismatches

Published Feb 23, 2021 · Updated Aug 3, 2024

Null pointer dereference in JasPer before 2.0.25 allows context-dependent attackers to crash an image-processing application via a crafted JP2 file. The jp2_decode function merely warns when JP2 header or BPCC component counts and types conflict with the decoded codestream, then continues into an invalid state that dereferences a null image pointer. A target application must process the crafted file, and the demonstrated consequence is interruption of that process rather than data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability1.09%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Null pointer dereference in JasPer before 2.0.25 allows context-dependent attackers to crash an image-processing application via a crafted JP2 file. The jp2_decode function merely warns when JP2 header or BPCC component counts and types conflict with the decoded codestream, then continues into an invalid state that dereferences a null image pointer. A target application must process the crafted file, and the demonstrated consequence is interruption of that process rather than data disclosure or modification.

The record

CVE
CVE-2021-26927
Published
Feb 23, 2021
Updated
Aug 3, 2024
Vendor
JasPer Project
Product
JasPer Image Coding Toolkit
Classifications
CWE-476
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=before 2.0.25

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

JasPer Project · JasPer Image Coding Toolkitversion=before 2.0.25

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P

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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-476NULL Pointer Dereference

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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