8.1

CVE-2026-42573: Svelte: XSS via DOM Clobbering of Internal Framework State

Modified
AliasesGHSA-rcqx-6q8c-2c42CGA-5m59-pvqx-x73cCGA-777q-h49r-ww58
Published 09-06-2026Last modified 15-07-2026

Vulnerability summary

CVE-2026-42573 is a high (CVSS 8.1) vulnerability in svelte. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 27.7% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.3, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.34%
0%100%
Low · -0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 09-06-2026
    PublishedVulnerability first disclosed.
  2. 15-07-2026
    Last modifiedVulnerability information updated.

Description

Svelte is a performance oriented web framework. Prior to version 5.55.7, Svelte was vulnerable to DOM clobbering of its internal framework state on elements, potentially leading to XSS attacks. This issue has been patched in version 5.55.7.

CVSS metrics

6 scores · 4 sources · 2 versions

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

28%

Versus all other CVEs

30-day change

Decrease -0.01 pp

From 0.35% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard3 products
  • langfuse-2-workerAll versions (No fix recorded)
  • langfuse-fips-2-workerAll versions (No fix recorded)
  • langfuse-fips-3.152-workerAll versions (No fix recorded)
Npm1 product
  • svelte< 5.55.7
Svelte1 product
Sveltejs1 product

4 vendors · 6 products

References

8 links