CVE-2026-54271
pbjs static codegen may emit attacker-controlled JS from crafted descriptors.
Is CVE-2026-54271 being exploited?
Not confirmed. CVE-2026-54271 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.30% probability of exploitation in the next 30 days.
How severe is CVE-2026-54271?
CVE-2026-54271 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-54271?
Yes. A fix has been recorded for CVE-2026-54271. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-54271 affect?
CVE-2026-54271 affects protobufjs-cli (versions < 1.3.2 and < 2.5.0). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-54271?
Upgrade to protobufjs-cli 1.3.2 or 2.5.0+
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Attacker-controlled JSON descriptors can inject code into generated JS; may execute when the file is run or imported.
Patch when possible
- affected< 1.3.2
- affected>= 2.0.0 and < 2.4.2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.