CVE-2023-5170Public exploitNetwork attack vector

Privileged-memory disclosure via mismatched canvas surface mapping

Published Sep 27, 2023 · Updated Feb 13, 2025

Memory disclosure in Mozilla Firefox before 118 allows remote attackers to leak privileged-process heap data during canvas rendering. CanvasTranslator cached a DataSourceSurface with SetPreparedMap, but GetPreparedMap accepted a replacement surface sharing the same mapped surface and returned non-corresponding heap memory to the content process. A compromised content process and leakage of useful data are required; the exposed memory can supply information for a sandbox escape, with no reported direct write or service interruption.

CVSS severity7.4
High
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory disclosure in Mozilla Firefox before 118 allows remote attackers to leak privileged-process heap data during canvas rendering. CanvasTranslator cached a DataSourceSurface with SetPreparedMap, but GetPreparedMap accepted a replacement surface sharing the same mapped surface and returned non-corresponding heap memory to the content process. A compromised content process and leakage of useful data are required; the exposed memory can supply information for a sandbox escape, with no reported direct write or service interruption.

The record

CVE
CVE-2023-5170
Published
Sep 27, 2023
Updated
Feb 13, 2025
Vendor
Mozilla
Product
Firefox
Classifications
CWE-401, T1211
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record 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=unspecified <118

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <118

Published CVSS scores

7.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N

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

CWE-401Missing Release of Memory after Effective Lifetime
T1211Exploitation for Defense Evasion

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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