Security Digest · Vulnerability record
CVE-2026-94545: Satori-generated SVG has improper escaping
Satori is a library to convert HTML and CSS to SVG.
CVSS 5.3 Medium EPSS 1.0% · p64 Patch this week
Should you act?
Normal patch cycle
No exploitation signal; fix it in your next routine update if you are affected. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 1.0%, percentile 64: FIRST’s model estimates a 1.0% chance of exploitation activity in the next 30 days, higher than 64% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Editorial verdict: Patch this week. Next.js: Windows, AVIF and next/og RCEs (Aug-Sep 2026) — Self-hosted Next.js apps still below 15.5.24 or 16.3.3 should upgrade now, ideally straight to the October releases; Windows hosts and apps optimizing untrusted AVIF images are the urgent cases.
What it is
Satori is a library to convert HTML and CSS to SVG. Starting in version 0.0.27 and prior to version 0.33.5, Satori does not properly escape certain values before including them in generated SVG output. This can allow crafted values to be interpreted as SVG markup. The impact depends on how the generated SVG is consumed. Version 0.33.5 contains a patch. No complete workaround exists besides upgrading. Applications that cannot immediately upgrade should not render attacker-controlled content with Satori.
Weakness type: CWE-116.
Product: vercel satori · Assigned by: GitHub_M · Published: 2026-09-30
Affected and fixed versions
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| vercel | satori | >= 0.0.27, < 0.33.5 |
| vercel | next | >= 16.2.0, < 16.3.6 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 4.0 | 5.3 Medium | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Attack requirements: present (depends on deployment conditions)
- Privileges required: none (no login)
- User interaction: passive
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable no, technical impact partial.
- FIRST EPSS (model of 2026-10-21): 1.04% probability of exploitation activity in the next 30 days; percentile 64.
Timeline
- — erroneo.us brief: Next.js: Windows, AVIF and next/og RCEs (Aug-Sep 2026)
- — CVE record last updated
- — CVE record published by GitHub_M
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- CVE.org record CVE-2026-94545 cve.org
- NVD entry CVE-2026-94545 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com