CyberSecBulletin
CVE-2022-36938NVD status: Modified

Redex: Improper Validation of Specified Quantity in Input

CVE-2022-36938 is a critical-severity improper validation of specified quantity in input vulnerability in Redex from Facebook, with a CVSS 3.1 base score of 9.8 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 3b44c64 as the first without the flaw, so updating Redex to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.5% chance of exploitation within 30 days, higher than 75% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Redex to 3b44c64 or a later version.
  2. 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
FacebookRedexbefore 3b44c643b44c64

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
LowNo special conditions are needed; the attack works reliably.
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
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalNVD
CVSS 3.19.8CriticalCISA (ADP)

Official description

DexLoader function get_stringidx_fromdex() in Redex prior to commit 3b44c64 can load an out of bound address when loading the string index table, potentially allowing remote code execution during processing of a 3rd party Android APK file.

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

The underlying weakness: Improper Validation of Specified Quantity in Input

The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties.

More Improper Validation of Specified Quantity in Input vulnerabilities (CWE-1284)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Validation of Specified Quantity in Input vulnerabilities

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