// For flags

CVE-2020-12417

Mozilla: Memory corruption due to missing sign-extension for ValueTags on ARM64

Severity Score

8.8
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

Due to confusion about ValueTags on JavaScript Objects, an object may pass through the type barrier, resulting in memory corruption and a potentially exploitable crash. *Note: this issue only affects Firefox on ARM64 platforms.* This vulnerability affects Firefox ESR < 68.10, Firefox < 78, and Thunderbird < 68.10.0.

Debido a una confusión acerca de ValueTags en objetos JavaScript, un objeto puede pasar a través de la barrera de tipo, resultando en una corrupción de la memoria y un bloqueo potencialmente explotable. *Nota: este problema solo afecta a Firefox en las plataformas ARM64. * Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 68.10, Firefox versiones anteriores a 78 y Thunderbird versiones anteriores a 68.10.0

The Mozilla Foundation Security Advisory describes this flaw as: Due to confusion about ValueTags on JavaScript Objects, an object may pass through the type barrier, resulting in memory corruption and a potentially exploitable crash.

An update that fixes 13 vulnerabilities is now available. This update for MozillaFirefox to version 78.0.1 ESR fixes the following issues. AppCache manifest poisoning due to url encoded character processing. Use-after-free in WebRTC VideoBroadcaster. Memory corruption due to missing sign-extension for ValueTags on ARM64. Information disclosure due to manipulated URL object. Use-after-free in nsGlobalWindowInner. Use-After-Free when trying to connect to a STUN server. RSA Key Generation vulnerable to side-channel attack. Add-On updates did not respect the same certificate trust rules as software updates. Integer overflow in nsJPEGEncoder::emptyOutputBuffer. DLL Hijacking due to searching %PATH% for a library. WebRTC permission prompt could have been bypassed by a compromised content process. Out of bound read in Date.parse. Memory safety bugs fixed in Firefox 78. This update was imported from the SUSE:SLE-15:Update update project.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2020-04-28 CVE Reserved
  • 2020-07-06 CVE Published
  • 2024-08-04 CVE Updated
  • 2024-08-04 First Exploit
  • 2025-05-23 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
  • CWE-617: Reachable Assertion
  • CWE-681: Incorrect Conversion between Numeric Types
  • CWE-787: Out-of-bounds Write
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Mozilla
Search vendor "Mozilla"
Firefox
Search vendor "Mozilla" for product "Firefox"
< 78.0
Search vendor "Mozilla" for product "Firefox" and version " < 78.0"
-
Affected
Mozilla
Search vendor "Mozilla"
Firefox Esr
Search vendor "Mozilla" for product "Firefox Esr"
< 68.10.0
Search vendor "Mozilla" for product "Firefox Esr" and version " < 68.10.0"
-
Affected
Mozilla
Search vendor "Mozilla"
Thunderbird
Search vendor "Mozilla" for product "Thunderbird"
< 68.10.0
Search vendor "Mozilla" for product "Thunderbird" and version " < 68.10.0"
-
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
16.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"
esm
Affected
Canonical
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Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
18.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "18.04"
lts
Affected
Canonical
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Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
19.10
Search vendor "Canonical" for product "Ubuntu Linux" and version "19.10"
-
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
20.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "20.04"
lts
Affected
Opensuse
Search vendor "Opensuse"
Leap
Search vendor "Opensuse" for product "Leap"
15.1
Search vendor "Opensuse" for product "Leap" and version "15.1"
-
Affected
Opensuse
Search vendor "Opensuse"
Leap
Search vendor "Opensuse" for product "Leap"
15.2
Search vendor "Opensuse" for product "Leap" and version "15.2"
-
Affected