libpng up to 1.6.56 Chunk Setter API png_set_hIST use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in libpng up to 1.6.56. This affects the function png_set_hIST of the component Chunk Setter API. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2026-34757. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in libpng up to 1.6.56. It has been rated as critical. This issue affects the function png_set_hIST of the component Chunk Setter API. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-34757. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 1.6.57 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libpng 1.6.57

Timelineinfo

04/09/2026 Advisory disclosed
04/09/2026 +0 days VulDB entry created
04/09/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-34757 (🔒)
GCVE (CVE): GCVE-0-2026-34757
GCVE (VulDB): GCVE-100-356507

Entryinfo

Created: 04/09/2026 11:12
Changes: 04/09/2026 11:12 (54)
Complete: 🔍
Cache ID: 216:FC7:103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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