CVE-2024-5695Network attack vector

Browser crash via ambiguous PHC realloc failure

Published Jun 11, 2024 · Updated Oct 30, 2024

Memory corruption in Firefox before 127 allows remote attackers to crash the browser through crafted content under low-memory conditions. MaybePageRealloc uses null for both a handled PHC allocation failure and an unhandled allocation, causing PageRealloc to pass a PHC pointer to mozjemalloc. Corruption requires attacker-influenced PHC allocations in specific positions; the usual consequence is a browser crash.

CVSS severity9.8
Critical
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in Firefox before 127 allows remote attackers to crash the browser through crafted content under low-memory conditions. MaybePageRealloc uses null for both a handled PHC allocation failure and an unhandled allocation, causing PageRealloc to pass a PHC pointer to mozjemalloc. Corruption requires attacker-influenced PHC allocations in specific positions; the usual consequence is a browser crash.

The record

CVE
CVE-2024-5695
Published
Jun 11, 2024
Updated
Oct 30, 2024
Vendor
Mozilla
Product
Firefox
Classifications
CWE-787, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 11, 2024CVE publishedPublication date reported by the CVE source.
  2. Oct 30, 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=unspecified <127

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <127

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1203Exploitation for Client Execution

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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