CyberSecBulletin
CVE-2022-1941NVD status: Modified

protobuf-cpp: Improper Validation of Syntactic Correctness of Input

Published Updated By the CyberSecBulletin desk

CVE-2022-1941 is a high-severity improper validation of syntactic correctness of input vulnerability in protobuf-cpp from Google, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 3.18.3, 3.19.5, 3.20.2 as the first without the flaw, so updating protobuf-cpp to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.51% chance of exploitation within 30 days, higher than 75% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update protobuf-cpp to 3.18.3 or 3.19.5 or 3.20.2 or 3.21.6, whichever matches your release line, or a later version.
  2. Update protobuf-python to 3.18.3 or 3.19.5 or 3.20.2 or 4.21.6, whichever matches your release line, or a later version.
  3. Read the advisory on github.com for workarounds and exact fixed builds.
  4. 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
Googleprotobuf-cpp3.16.1 and earlier; 3.17.3 and earlier; 3.18.2 and earlier; 3.19.4 and earlier; 3.20.1 and earlier; 3.21.5 and earlier; before 3.18.3; 3.19.0 up to, but not including, 3.19.5; and 2 more ranges3.18.3, 3.19.5, 3.20.2, 3.21.6
Googleprotobuf-python3.16.1 and earlier; 3.17.3 and earlier; 3.18.2 and earlier; 3.19.4 and earlier; 3.20.1 and earlier; 4.21.5 and earlier; before 3.18.3; 3.19.0 up to, but not including, 3.19.5; and 2 more ranges3.18.3, 3.19.5, 3.20.2, 4.21.6
Fedora ProjectFedora36; 37Not stated
DebianDebian Linux10.0Not stated

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
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official description

A parsing vulnerability for the MessageSet type in the ProtocolBuffers versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 3.21.5 for protobuf-cpp, and versions prior to and including 3.16.1, 3.17.3, 3.18.2, 3.19.4, 3.20.1 and 4.21.5 for protobuf-python can lead to out of memory failures. A specially crafted message with multiple key-value per elements creates parsing issues, and can lead to a Denial of Service against services receiving unsanitized input. We recommend upgrading to versions 3.18.3, 3.19.5, 3.20.2, 3.21.6 for protobuf-cpp and 3.18.3, 3.19.5, 3.20.2, 4.21.6 for protobuf-python. Versions for 3.16 and 3.17 are no longer updated.

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

The underlying weakness: Improper Validation of Syntactic Correctness of Input

The product receives input that is expected to be well-formed - i.e., to comply with a certain syntax - but it does not validate or incorrectly validates that the input complies with the syntax.

More Improper Validation of Syntactic Correctness of Input vulnerabilities (CWE-1286)

Timeline

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

References

Third-party and government advisories

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