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Vulnerability details: VCID-ycam-n781-gkf8
Vulnerability ID VCID-ycam-n781-gkf8
Aliases CVE-2026-42567
GHSA-9rmh-mm8f-r9h6
Summary Svelte is a performance oriented web framework. From version 5.51.5 to before version 5.55.7, an internal regex in the Svelte runtime can take exponential time to test in <svelte:element this={tag}></svelte:element>. This issue has been patched in version 5.55.7.
Status Published
Exploitability 0.5
Weighted Severity 6.2
Risk 3.1
Affected and Fixed Packages Package Details
Weaknesses (3)
CWE-1333 Inefficient Regular Expression Complexity
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3 5.9 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-42567.json
epss 0.00039 https://api.first.org/data/v1/epss?cve=CVE-2026-42567
epss 0.00047 https://api.first.org/data/v1/epss?cve=CVE-2026-42567
epss 0.00047 https://api.first.org/data/v1/epss?cve=CVE-2026-42567
cvssv3.1_qr MODERATE https://github.com/advisories/GHSA-9rmh-mm8f-r9h6
cvssv4 5.9 https://github.com/sveltejs/svelte
generic_textual MODERATE https://github.com/sveltejs/svelte
cvssv4 5.9 https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
generic_textual MODERATE https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
ssvc Track https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
cvssv3.1_qr MODERATE https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
cvssv4 5.9 https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
generic_textual MODERATE https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
ssvc Track https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
cvssv4 5.9 https://nvd.nist.gov/vuln/detail/CVE-2026-42567
generic_textual MODERATE https://nvd.nist.gov/vuln/detail/CVE-2026-42567
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-42567.json
https://api.first.org/data/v1/epss?cve=CVE-2026-42567
https://github.com/sveltejs/svelte
https://nvd.nist.gov/vuln/detail/CVE-2026-42567
2487114 https://bugzilla.redhat.com/show_bug.cgi?id=2487114
GHSA-9rmh-mm8f-r9h6 https://github.com/advisories/GHSA-9rmh-mm8f-r9h6
GHSA-9rmh-mm8f-r9h6 https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
svelte%405.55.7 https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-42567.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N Found at https://github.com/sveltejs/svelte
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N Found at https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-06-09T18:09:08Z/ Found at https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N Found at https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-06-09T18:09:08Z/ Found at https://github.com/sveltejs/svelte/security/advisories/GHSA-9rmh-mm8f-r9h6
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N Found at https://nvd.nist.gov/vuln/detail/CVE-2026-42567
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.11899
EPSS Score 0.00039
Published At June 11, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-06-11T16:44:22.147163+00:00 Vulnrichment Import https://github.com/cisagov/vulnrichment/blob/develop/2026/42xxx/CVE-2026-42567.json 38.6.0