CVE-2026-34975
CRLF header injection in Plunk SES integration.
Is CVE-2026-34975 being exploited?
Not confirmed. CVE-2026-34975 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 0.19% probability of exploitation in the next 30 days.
How severe is CVE-2026-34975?
CVE-2026-34975 is rated High with a CVSS score of 8.5. 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-2026-34975?
Yes. A fix has been recorded for CVE-2026-34975. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-34975 affect?
CVE-2026-34975 affects Plunk SESService.ts (pre-0.8.0), Plunk (pre-0.8.0). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-34975?
Upgrade to 0.8.0+; sanitize inputs
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated API user can inject CRLF headers (e.g., Bcc, Reply-To), enabling spoofing and silent forwarding.
Patch when possible
- affected< 0.8.0
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.