Skip to main content

Boteraser | Website and Server Security Solutions

🛡️ CVE-2026-44293 — protobufjs

🟠 CVSS 8.0 — High ✅ No Known Exploit CWE-94 OSV
8.0
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

protobuf.js: Code injection through bytes field defaults in generated toObject code

Summary

protobufjs generated JavaScript for toObject conversion could include an unsafe expression derived from a schema-controlled bytes field default value. A crafted descriptor with a non-string default value for a bytes field could cause attacker-controlled code to be emitted into the generated conversion function.

Impact

An attacker who can provide or influence a protobuf descriptor may be able to execute arbitrary JavaScript in the context of the process using protobufjs.

This requires the application to load an attacker-controlled schema or descriptor and then convert a message of the affected type with defaults enabled. Applications that only use trusted, application-defined schemas are not directly affected by this issue.

Preconditions

  • The application must allow an attacker to control or influence a protobuf JSON descriptor or equivalent reflected schema.
  • The descriptor must define a bytes field with an attacker-controlled default value.
  • The application must call toObject with defaults enabled for the affected type.

Workarounds

Do not load protobuf schemas or JSON descriptors from untrusted sources with affected versions. If untrusted schemas must be accepted, validate or restrict field options before loading them and run schema processing in an isolated environment.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. Rated impact: confidentiality high, integrity high, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: Low — the attack works reliably, with no preparation.
  • Attack requirements: Present — the target has to be in a particular state for the attack to work.
  • Privileges required: Low — an ordinary user account is enough.
  • User interaction: None — nobody has to be tricked into anything.
  • Confidentiality impact: High — total loss, or loss the attacker controls.
  • Integrity impact: High — total loss, or loss the attacker controls.
  • Availability impact: High — total loss, or loss the attacker controls.

Weakness class

CVE-2026-44293 is classified as CWE-94: Code Injection. Input is incorporated into code that the runtime evaluates, so an attacker can have their own code executed.

Affected software

CVE-2026-44293 is recorded against 1 package.

  • protobufjs

Timeline and source

Published on 12 May 2026 and last revised on 19 August 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

github.com (Web)
github.com (Package)
github.com (Web)
github.com (Web)

Other advisories for this package

protobufjs has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-94: Code Injection) in other software:

CVE-2026-44293 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity HIGH
CVSS Score 8.0
CVSS Vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CWE CWE-94
Public Exploit ✅ No
Source OSV
Published 2026-05-12
Updated 2026-08-20
Modified 2026-08-19
Fix URL N/A

Affected Packages

Software From version Fixed in
protobufjs — —

Site Security Check

Is protobufjs part of your stack?

CVE-2026-44293 is rated CVSS 8.0 High. BotEraser scans your installation against known CVE records and tells you whether this vulnerability applies to the versions you actually run.

Scan My Site Free →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

Browse related advisories

All advisoriesCVECVE 2026
✓