CyberSecBulletin
CVE-2024-6603NVD status: Analyzed

Firefox: Use of Out-of-range Pointer Offset

Published Updated By the CyberSecBulletin desk

CVE-2024-6603 is a high-severity use of out-of-range pointer offset vulnerability in Firefox from Mozilla, with a CVSS 3.1 base score of 7.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 128 as the first without the flaw, so updating Firefox to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.54% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Firefox to 128 or a later version.
  2. Update Firefox ESR to 115.13 or a later version.
  3. Update Thunderbird to 115.13 or 128, whichever matches your release line, or a later version.
  4. Read the advisory on mozilla.org for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
MozillaFirefoxbefore 128128
MozillaFirefox ESRbefore 115.13115.13
MozillaThunderbirdbefore 115.13; before 128115.13, 128

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by CISA (ADP).

Official description

In an out-of-memory scenario an allocation could fail but free would have been called on the pointer afterwards leading to memory corruption. This vulnerability affects Firefox < 128, Firefox ESR < 115.13, Thunderbird < 115.13, and Thunderbird < 128.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Out-of-range Pointer Offset

The product performs pointer arithmetic on a valid pointer, but it uses an offset that can point outside of the intended range of valid memory locations for the resulting pointer.

More Use of Out-of-range Pointer Offset vulnerabilities (CWE-823)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other references

Other vulnerabilities in Firefox

All Firefox vulnerabilities

Recent Use of Out-of-range Pointer Offset vulnerabilities

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