CVE-2020-36277Network attack vector

Application crash via incorrect pixel-data left shift

Published Mar 11, 2021 · Updated Aug 4, 2024

Always-incorrect control flow in Leptonica before 1.80.0 allows remote attackers to crash applications via crafted 2 bpp images. The pixConvert2To8 function in pixconv.c performs an incorrect left shift while expanding 2-bit pixels into 8-bit values. Reachability requires attacker-controlled image data to enter this conversion path; exploitation terminates the processing application without reported data disclosure or modification.

CVSS severity7.5
High
EPSS probability2.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Always-incorrect control flow in Leptonica before 1.80.0 allows remote attackers to crash applications via crafted 2 bpp images. The pixConvert2To8 function in pixconv.c performs an incorrect left shift while expanding 2-bit pixels into 8-bit values. Reachability requires attacker-controlled image data to enter this conversion path; exploitation terminates the processing application without reported data disclosure or modification.

The record

CVE
CVE-2020-36277
Published
Mar 11, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-670
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 11, 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

7.5GitLab Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-670Always-Incorrect Control Flow Implementation

Public exploit references

No public exploit references are available in this record.

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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